agetty is a small version of getty, usefull only to login on virtual
console or serials port. Sintassi: agetty [optios] < velocity > [,... ]
< port > [tarminal] Opzioni: "port" is the device to use, like
tty1 if you want to use /dev/tty1 "velocity" a comma
separated list of bps velocity. "terminal" the kind of terminal
emulation to use Options -h enable hardware control, i.e. RTS/CTS -i don't
show the content of /etc/issue before the user logon -f < file > specify
a diffent file to use instead of /etc/issue -I
initialization string to send to the terminal -l
specify a differnt program instead of /bin/login -m try to autoscan for the
modem transmission velocity -t
login timeout in seconds -w Wait for
or
before to send the issue file
-----------------------------------------------------------------------
Define an alias for a command. Typeing alias with no arguments cause to
show the list of all the aliases Typeing an alias with no value cause to erase
the alias for that name When defining a new alias there must be no blank-space
between the name and the value Sintassi: alias [< name > [= < value
> ] ... ] Example: alias dir='ls -al'
-----------------------------------------------------------------------
alien converts packages between different distribution into Debian o
RedHat formats. Sintassi: alien {--to-deb | --to-rpm} [options] <
package_name >
----------------------------------------------------------------------
Search into the 'whatis' database, that contain info about the command
system, for one or more words. The 'whatis' database is generated thru' the
command 'makewhatis'. apropos, instead of whatis, display all the string that
match with the search pattern instead of only the first.
-----------------------------------------------------------------------
Schedule a command for a single execution Sintassi: at [option] [datetime]
Opzioni:
[AM|PM] or
[AM|PM] today tomorrow
|
|
.
.
now
+
+ < minutes | hours | days | weeks > -q < a..z> Specify the letter
that identify the "queue" where to put the job -m Send a mail when
the job is executed -f < file > Get the command to run from this file -l
Act as 'atq' -d Act as 'atrm' -b Act as 'batch' -v In 'atq' mode let to know
the execution time (1) at -f file_name [-m] time [date] "file_name"
is the script to be executed "-m" send a mail message when the
command is has been executed "time" must be in the format hh:mm am/pm
or can be 'midnight' or in the form 'now+h' "date" must be in the
form "Dec 25 1994" (2) at -l list the command scheduled (3) at -r
job delete the scheduled command
-----------------------------------------------------------------------
This program is used internally by "cron" to see if there are
jobs pending on the "at" or "batch" tail. It usually is
run every minutes.
-----------------------------------------------------------------------
An interpreted language, very usefull for text manipulation and shell
script. Synonims are gawk and nawk
-----------------------------------------------------------------------
* B *
-----------------------------------------------------------------------
badblock is used to check the low-level integrity of a disk or partition,
i.e. it check for bad blocks/clusters Sintassi: badblocks [optons] < device
> < number_of_blocks > [first_block] Opzioni: -b < block_size >
Tell the size of every block. Default value is 1024 -w LOW-LEVEL FORMAT YOUR
DRIVE, DO NOT USE !!!! Esempi: badblocks /dev/fd0 1440
-----------------------------------------------------------------------
Generate on the stdout a banner of the text specified on the command line.
It is genereally used to print banners.
-----------------------------------------------------------------------
Bourne Again SHel This is just your shell, i.e. the "command.com"
for windoze addicted Shortcut Effect Up Arrow Scroll the history backward Dn
Arrow Scroll the history forward Left Arrow Move cursor back Right Arrow Move
cursor forward Ctrl+b Move cursor back Ctrl+f Move cursor forward Backspace
BackSpace Ctrl+d Delete a char Ctrl+a Move cursor to the start of the line
Ctrl+e Move cursor at the end of the line Alt+f Move cursor one word forward
Alt+b Move cursor one word backward Ctrl+l Clear the screen
-----------------------------------------------------------------------
Strip the path from a filename, and eventually also the suffix Sintassi:
basename < pathname > [suffix] Esempi: basename /home/denny/test.awk
Return "test.awk" basename /home/denny/test.awk .awk Return
"test"
-----------------------------------------------------------------------
A job scheduler, the syntax is the same as 'at' but a job is executed only
if the system is not heavy loaded.
-----------------------------------------------------------------------
Display one or more files, usually is also used to append one file to
another. Sintassi: cat [ option ] < file(s) > Examples: cat firstfile
secondfile cat head body tail > dog Opzioni: "-A" "--show-all"
show all the non-printable chars, act like "-vET" "-b"
"--number-nonblank" number all the nonblank lines starting from 1
"-E" "--show-ends" append the symbol "$" at the
end of each line "-s" "--squeeze-blank" substitute
multiple blanklines with only one "-T" "--show-tabs"
substitute the
char with the symbol "^I" "-v" "--show-nonprinting"
convert all the non-printable chars into a visible form
-----------------------------------------------------------------------
Change the current directory Esempi: cd /tmp Goes into the directory tmp
cd ~ Go into the user's home directory cd ~kim Goes into the kim's home
directory cd .. Goes to the higher level directory
-----------------------------------------------------------------------
cfdisk is like "fdisk" eccept that it use an interactive
interface. Sintassi: cfdisk [options] [device]
-----------------------------------------------------------------------
This program change the attributes of a file on a Ext2 filesystem
Sintassi: chattr [options] [mode] < file > Options/Attributes:
"+" Add the following attribute to the file "-" Remove the
following attribute from the file "A" Tell to not update the access
time (aime). This reduce the disk activity "a" Tell that a file can
be only open in "append" mode when someone want to write
"c" Let the kernel manage compression/decompression on the file (NOT
IMPLEMENTED YET!) "d" Tell to the dump program that this program
must no be backup-ed "i" The file is "immutable"
"s" When the file is delete the block occupated by it are filled
with zero. "S" Syncronize all the operation upon this file, without
using the disk cache "u" Let undelete this file (NOT IMPLEMENTED YET!)
-----------------------------------------------------------------------
Let to change the "finger" (name, address, telephone)
information stored into /etc/passwd Sintassi: chfn [options] [user]
-----------------------------------------------------------------------
Change the group that own a file or directory. See "chown" for
the complete syntax Sintassi: chgrp [options] [group] Opzioni: "-R"
Change the permission into every sub-directory
-----------------------------------------------------------------------
Change the permissions upon the specified file or directory Sintassi:
chmod [options] < mode > < file > Opzioni: "-R" change
the permission into the subdirectories Mode Sintassi: [ugoa][[+-=][rwxXstugo]
"u" the user that own the file "g" the group that own the
file "o" the other users "a" everybody "+" add
those permissions "-" remove those permissions "=" assign
those permissions "r" Add the read permission "w" Add the
write permission "x" Add the execute permission "X"
"s" "t" Enable the sticky bit. "u" Set the same
permission has the user that own the file "g" Set the same
permission has the group that own the file "o" Set the same
permission has the "other" user
-----------------------------------------------------------------------
Change the user that own a file Sintassi: chown [options] [user][:|.][group]
file Opzioni: "-R" change the permission into the subdirectories
-----------------------------------------------------------------------
Let you change the predefinite shell into /etc/passwd. It is possible to
set only an existing shell, mentioned into /etc/shells Sintassi: chsh [options]
[user] Opzioni: "-s
" "--shell
" Let you specify a shell "-l" "--list-shells"
Display the content of /etc/shells
-----------------------------------------------------------------------
Change the current Virtual Terminal, i.e. switch the terminal like ALT +[Fn]
programmatically
-----------------------------------------------------------------------
Access the hardware clock of the machine Sintassi: clock [-u] [-r | -w |
-s | -a] Opzioni: "-u" Set the clock in Universal Time (UTC)
"-r" Display the hardware clock "-w" Update the system
clock with the hardware clock "-s" "-a" Update the system
clock with the hardware clock in conjunction with the error adjustment
specified into /etc/adjtime Esempi: clock -w Update the system clock with the
value into the BIOS
-----------------------------------------------------------------------
Old Compression utility, generate a file with .Z suffix. To unzip use
uncompress Sintassi: compress [-v] < file_name > "-v" display
the compression rate
-----------------------------------------------------------------------
Copy one or more file or directory Sintassi: cp [option] < source >
< target > "-a" same as "-dpR", make an exact copy
of everything (include symlink) "-b" maintain a backup copy of every
file that is overwritten "-d" or "--no-deference" copy
symlinks without the linked file "-f" or "--force" force
overwrite of the target file "-i" or "--interactive" ask
for confirmation before overwite any file "-l" or "--link"
make hard-link instead of copy file "-P" or "--parents"
Copy the path specified into the source "-p" or "--preserve"
keep orignal date, owner and permission "-r" recursive copy every
subdirectory, every file is considered normal "-R" or "--recursive"
recursive copy every subdirectory "-s" or "--symbolic-link"
make a symlink instead of copy the file (not true for directory) "-S <
backup_suffix >" or "--suffix=
" Specify a suffix to use when making backup copies of overwritten files
"-V < backup_type >" or "--version-control=<
backup_type >" Specify how to handle backup copies Backup Types:
"t" "numbered" number every backup copy "nil"
"existing" perform a numbered backup for only the file that already
have been backup-ed with "t" "never" "simple"
perform a simple backup, non numbered copy just only one Environment Variables:
VERSION_CONTROL Contain the backup type. SIMPLE_BACKUP_SUFFIX Contain the
suffix to use when making a "simple" backup Examples: cp -r /test/*
~/test cp -dpR /test ~/test
-----------------------------------------------------------------------
Manage archive of files, like TAR. cpio is used instead of cp or other
tools because: - It can access tape drives on other hosts using TCP/IP. - `-o'
and `-p' can copy symbolic links either as symbolic links or, with `-L', as
the files they point to. - `-i' automatically recognizes the archive format
and tries to recover from corrupted archives. - The output of '-itv' looks
like 'ls -l'. - It accepts long-named options as well as traditional
single-character options. Syntax "copy-out " : cpio -o [options]
[< name list] [>
] Read from the standard input a list of names (one for line) that are
archived to the standard output Syntax "copy-in" : cpio -i [options]
[
] [<
] Read from the standard input the name of the archive from wich extract the
files Syntax "copy-pass" : cpio -p [options] < target dir >
[< name list >] Read from the standard input a list of names (one for
line) that are copied to the destination directory Opzioni: "-o"
"--create" copy-out "-A" "--append" Append data
to an archive specified with the "-O" option "-L" "--dereference"
copy only the symlink not the file "-O < archive name >"
Specify the name of the archive to create or append instead of the standard
output "-i" "--extract" copy-in "-d" "--make-directories"
"-E < file >" "--pattern-file=< file >" Read a
model that list the file to extract "-f" "--nomatching"
Copy the files that do not match with the specified model "-I <
archive >" Specify the name of the archive to use instead of the
standard input "-t" "--list" List the content of an
archive "-p" "--pass-through" copy-pass "-d"
"--make-directories" "-l" "--link" create link
instead of copy the files "-L" "--dereference"
-----------------------------------------------------------------------
Let you modify the "crontab" file for a specified user. The
crontab file is used by the daemon cron (a system scheduler) to run specified
program at a given time. "crontab -l" view the current crond
settings Sintassi: crontab [options] [file] Opzioni: -u
Replace the crontab of the user with the specified file -l
View the crontab of that user -e
Create or modify the crontab of the user -r
Delete the crontab of the user
-----------------------------------------------------------------------
Show/modify the current system's date and/or time Sintassi: date [options]
[+ format] [date] Opzioni: "-d < date >" "--date=
" Display the date-time "-s < date >" "--set=
" Set the new system's date-time "-u" "--universal"
Display or set the date-time in universal time (UTC) Examples: date + "%r"
display only the time date + "%D" display only the date Formats: %%
Show a "%" %n newline %t tab %s number if second from the specified
epoch %c same as the string "%a %b %d %X %Z %Y" %H hour in format
00..23 %I hour in format 00..12 %k hour in format 00..23 %l hour in format
00..12 %M minutes in format 00..59 %S seconds in format 00..59 %p AM or PM %Z
include timezone %r time in 12 hour format ``hh:mm:ss AM/PM''. %T time in 24
hour format ``hh:mm:ss'' %X time like the string "%H:%M:%S" %a short
week day name %A long day name %U week of the year, between 00..53 %w day of
the week, between 0..6 where 0 is sunday %b Show month name %h like %b %B long
month name %m month in format 00..12 %y year in format 00..99 %Y year in
format 0000..9999 %d day of the month in format 00..31 %j day of the year in
format 01..366 %D date in format `mm/gg/aa' %x local date view
-----------------------------------------------------------------------
dd (Data Dublicator or Data Dump) is a low level copy program. Sintassi:
dd [options] Opzioni: if=< file > Specify the input file or device
of=< file > Specify the output or the device ibs=
Specify a block size in byte for the input file obs=
Specify a block size in byte for the ouput file bs=
Ovveride both ibs and obs parameters cbs=
Specify the dimension of the buffer used to convert the file skip=
Specify how many block to skip before to start reading from the input file
seek=
Specify how many block to skip before to start writing to the output file
count=
Specify the amount of block to be copied conv=
[,
]... Specify one or more conversion step Conversion types: ascii Convert from
EBCDIC to ASCII. ebcdic Convert from ASCII to EBCDIC. ibm Converte from
ASCII-IBM to EBCDIC. block Treat the input file like a set of record that end
with the "newline" char. This record are trunced or expanded to fit
the dimension of a block upon the output file unblock Every block of the input
file is readed and the final spaces are substituted with a newline char. lcase
Trasform from uppercase to lowercase ucase Trasform from lowercase to
uppercase swab Exchange pair of byte, i.e. from bigendian to littleendian and
viceversa noerror Ignore every error into the reading of the input file
notrunc The output file isn't truncated if it is bigger than the required
space sync Adjust the lenght of every input block adding a newline char at the
end Suffixes: Every option that require a byte value or block lenght can be
take a suffix to specify a greate quantity. These are: "b" specify
block of 512 byte "c" char (1byte) "k" size is expressed
in kilobyte (1024 bytes) "w" size is ( n * 2 ) "x
" size is ( n * m ) Exampes: dd if=/vmlinuz of=/dev/fd0 This copy the
kernel upon your floppy disk dd if=/vmlinuz of=/dev/fd0 obs=18k Same as above,
but 3"1/2 floppy disk use a block size of 18 KB dd if=disk.img of=/dev/fd0
Copy an image upon floppy
-----------------------------------------------------------------------
'depmod -a' will create the file 'modules.dep' under '/lib/modules'. This
file is used to find the kernel modules by the "kerneld" daemon
-----------------------------------------------------------------------
The dev directory contain special files that permit direct access to the
hardware /dev/fd0 first floppy unit /dev/hda first IDE/EIDE hard disk /dev/hda1
first partition on the first IDE/EIDE hard disk /dev/hdb second IDE/EIDE hard
disk /dev/sda fisrt SCSI hard disk /dev/sda1 first partition on the fisrt SCSI
hard disk /dev/lp0 first parallel port /dev/lp1 second parallel port /dev/cua0
first serial port, i.e. COM1: /dev/ttyS0 first serial port, only in input /dev/null
the NULL device, every read or write has no effect
-----------------------------------------------------------------------
Display the amount of free space on the disks Sintassi: df [options] [device]
Opzioni: "-a" "--all" Show info upon all the devices
"-b" "--byte" Display memory in bytes "-h"
"--human-redable" Display info into "human readable" form
:-) "-i" "--inodes" Display size into inode "-k"
"--kilobytes" Display memory in kilobytes "-m" "--megabytes"
Display memory in megabytes
-----------------------------------------------------------------------
Compare two text files and create a 'diff' file to be used by the patch
program to apply them. Used widely into the kernel (or large) development
project Sintassi: diff [-b] [-i] [-w] < file or dir > < file or dir
> "-b" treath multiple blank/spaces as only one "-i"
ignore the char case "-r" recurse subfolders "-w" ignore
tabs and space
-----------------------------------------------------------------------
Configure the color for the 'ls' command. Use: eval `dircolors [options]
[file] Opzioni: If a file is not specified then dircolors try to use first ~/.dir_colors
then it look for /etc/DIR_COLORS
-----------------------------------------------------------------------
Display the list of the directories stored into a stack. To save/restore a
dir the command 'pushd' and 'popd' are used Sintassi: dirs [-l] [+/-n]
Opzioni: "+n" Show only "n" elements form the top of the
stack "-n" Show only "n" elements form the bottom of the
stack "-l" Show the list into the "long" format
-----------------------------------------------------------------------
Return the directory name from a filename specified in input Sintassi:
dirname < file_name >
-----------------------------------------------------------------------
Display the amount of space used by a directory or a file Sintassi: du [options]
[dir or file ] Opzioni: "-a" "--all" Show info upon all
the devices "-b" "--byte" Display memory in bytes
"-c" "--total" Display a general total "-h"
"--human-redable" Display info into "human readable" form
:-) "-i" "--inodes" Display size into inode "-k"
"--kilobytes" Display memory in kilobytes "-m" "--megabytes"
Display memory in megabytes "-s" "--summarize" Display a
total for every argument "-S" "--separate-dirs" Do not
display the space used by subdirs "-x" "--one-file-system"
Do not go into different filesystem mounted on some subdirs
-----------------------------------------------------------------------
echo a string to the standard output Sintassi: echo [options] "string"
Opzioni: "-n" do not start a new line "-e" enable parsing
of escape sequences "-E" enable parsing of escape sequences Escape
sequences: \a bell \b backspace; \c suppress the final newlin char \f form
feed \n newline \r carriage return \t tab \v vertical tab \\ backslash \ooo a
char code into octal system
-----------------------------------------------------------------------
Let you assign and modify the "quota" for every user. This need
the presence of the files quota.user and quota.group Sintassi: edquota [options]
[user] Opzioni: "-u" Modify the user quota "-g" Modify the
group quota "-p
egrep
Tee "E"xpanded version of "grep"
-----------------------------------------------------------------------
Exit, exits from a shell, from a "su" session, from a console
and many more ...
-----------------------------------------------------------------------
Format a floppy disk at low-level Sintassi: fdformat [-n] < device_name
> Esempi: fdformat /dev/fd0 Format the disk into your drive A:
-----------------------------------------------------------------------
fdisk is a program to edit the partition table of your HD If you don't
know what i'm talking about don't use it ! You may delete everything on your
PC !! Sintassi: fdisk [options] [device] Opzioni: -l List all the partition on
hard-disk IDE and SCSI -s < partition > Get the size of that partition
-----------------------------------------------------------------------
Tell you what kind of file is the one you specified. Require the file /etc/magic
Sintassi: file [options] < filename >
-----------------------------------------------------------------------
Search for one or more file and output his/their complete path Sintassi:
find < starting_path > [options] Opzioni: "-atime +days"
search file not accessed for n days "-depth" start from the last
subdirectoy instead that from the root "-exec command \;" for every
file execute a command "-iname < file_name >" search for a
case-insensitive pattern "-mtime +days" search file not modified for
n days "-name < file_name >" search for a case-sensitive
pattern "-noleaf" do not optimize the search, to be used on cd-rom
"-ok command \;" for every file execute a command asking user
confirmation "-print" "-user < user_name > " "-xdev"
search only into this Filesystem, does not search into mounted subdirectory
(i.e., cdroms, NFSs)
-----------------------------------------------------------------------
Show the amount of free memory (RAM) Sintassi: free [options] Opzioni: -b
Show size in bytes -k Show size in kilobytes -t Show a line with totals -o
Disable buffer adjusting -s
update results each the nr. of secs.
-----------------------------------------------------------------------
Check the integrity of a filesystem. This is a front-end to a serie of
fsck.* files like (fsck.ext2, fsck.dos, fsck.xia, ecc.) Sintassi: fsck [options]
[-t
] [
]
-----------------------------------------------------------------------
This command, also know as "e2fsck", check an ext2 filesystem
Sintassi: fsck.ext2 [options]
Opzioni: -c Use "badblocks" to check damaged block -f Force the
checking f the fs -F Flush the disk cache before to start checking -n Perform
a read-only control without changing anything -p Perform an automatic repair
of the filesystem -y like -p Exit status: 0 no errors 1 errors 2 errors upon a
mounted FS, need reboot 4 errors not fixed
-----------------------------------------------------------------------
This command, also know as "dosfsck" let you check a DOS-FAT16
filesystem. Sintassi: fsck.msdos [options]
Opzioni: -a Perform an automatic repair of the filesystem -r Interactive
repair of the filesystem -t mark not-readable cluster as bad-blocks Exit
status 0 no errors 1 found solvable errors 2 syntax errors
-----------------------------------------------------------------------
Tell wich user is locking a file Sintassi: fuser [options] < file >
Opzioni: -a Show all the listed files not only the used once -k Kill all the
process that are using that files -
Send the
signal to the process who are using the file -m Means that the file is a
device -u Tell the user that is owning the process who own the file -v Use a
table format to show file in use -s Suppress output
-----------------------------------------------------------------------
* G *
-----------------------------------------------------------------------
Getty is a program that is run at boot time. It let you login on your
system. Sintassi: getty [options]
[
[type] ] Opzioni: "-c
" Check the syntax of a gettydefs file, like /etc/gettydefs "-d
" Specify a configuration file rather tha /etc/gettydefs "-r
" Second to delay before to display the login message "-w
" Set a string to wait before to start to displaying the login prompt
"-t
" Set the timeout for the login Example (/etc/inittab) : # Start getty to
listen on the first virtual console 1:12345:respawn:/sbin/getty tty1 # Start
getty to listen on the second serial line s1:2345:respawn:/sbin/getty ttyS1
DT19200 vt100
-----------------------------------------------------------------------
A daemon to handle mouse selection, and also cut & past, in textmode
Sintassi: gpm [options] Opzioni: -B < button order sequence > Set the
button order sequence -t < type > Set the mouse type -2 Force a 2 button
mouse -3 Force a 3 button mouse -S "command1:command2:command3" Set
commands for the mouse "triple-click" Mouse types: mman Mouseman. ms
Microsoft with 2 or 3 button bare Microsoft with 2 button msc MouseSystem with
3 button sun MouseSystem variant mm MMSeries logi Logitech serial mouse bm
Microsoft BusMouse or compatible ps2 IBM PS/2 Busmouse and compatible (the
ones with a circular connector) ncr NCR3125pen. wacom Wacom graphical table
-----------------------------------------------------------------------
Change the shadow-password for a group stored into /etc/gshadow The
password for a group is used to let users that are not member of this group to
become parts of it by the command "newgrp" Sintassi: gpasswd [options]
Opzioni: -A
Modify the list of the administrators for that group -M
Modify the list of user part of that group -a
Add a user for that group -d
Let an administrator to delete a member -r
Let an administrator to delete a password -R Let an administrator to disable
access through the use of password
-----------------------------------------------------------------------
Search for a pattern into one or more files Syntax "grep": grep
[options] text_pattern file_names Syntax "egrep": grep [options] -e
text_pattern file_names Syntax "ggrep": grep [options] -f
text_pattern file_names Opzioni: "-c" output only the total of line
matching the expression "-E" use an extended regular expression
"-e" Specify a model to search "-F" use a fixed string
model "-f" specify a file with the model "-G" use a normal
regular expression "-h" suppress heading "-i" case
insensitive "-l" display the name of the non-matching files
"-l" display only the files name that content match the expression
"-n" append the number of line "-v" search for lines that
does not contain the text "text_pattern" can contain the following
special chars "^" search for the text at the starting of the line
"$" search at the end of the line
-----------------------------------------------------------------------
Show the groups list or the group wich a user is member This command is
the same as "id -Gn [user] " Sintassi: groups [users]
-----------------------------------------------------------------------
Check the syntax of the file /etc/group and of /etc/gshadow (using also /etc/passwd
Sintassi: grpck [-r] [
[
]] "-r" force to program to not make any changes only to output
problem -----------------------------------------------------------------------
Convert the group file /etc/group into /etc/group and /etc/gshadow
Sintassi: grpconv
-----------------------------------------------------------------------
UnConvert the shadow password to the normal group /etc/group At the end
the file /etc/gshadow is erased. Sintassi: grpunconv
-----------------------------------------------------------------------
Uncompress a .gz file, compressed with gzip Esempi: gunzip -d
backup.tar.gz will return "backup.tar" and erase backup.tar.gz
-----------------------------------------------------------------------
Compress one file. To unzip use the gunzip command Sintassi: gzip [options]
[file] "-9" use the maximum compression value "-c" ouput
the result to the standard output "-d" force decompression instead
of compression "-r" recursively compress every file into a
sub-directory "-t" check the integrity of compressed files Esempi:
gzip -9 backup.tar create "backup.tar.gz" and will erase backup.tar
* H *
-----------------------------------------------------------------------
Display the user's ID (UID) or the group ID (GID) Sintassi: id [options] [user]
Opzions: "-u" "--user" Display only the UID "-g"
"--group" Display only the GID "-G" "--groups"
Display only the numbers of extra group "-n" "--name"
Display only the user or group name "-r" "--real" Display
only the real UID/GID
-----------------------------------------------------------------------
Init is the first task that the kernel execute. His job is to start,
according to the choosen runlevel, the script for starting, stopping or
rebooting the system. Sintassi: init [options] Opzioni: -t
Nr. of seconds to wait before to change "runlevel" 0..6 Change to a
runlevel between 0 and 6 a|b|c Run one of the "on demand" level q
ReScan /etc/inittab s Go into single user
-----------------------------------------------------------------------
A text-base reader for "info" documentation Sintassi: info [options]
[voice] Opzioni: --directory
Specify where to find info files -f < file > Specify an info file -n
Specify a particular node Keyboard Shortcuts: q Quit the program h View the
on-line help ? View the list of all available command d View the 'dir' file l
Return back to the previous node n View the next node p View the previous node
u View the upper node SPACE Scroll the node forward CANC Scroll the node
backward b Go to the beginning of the node TAB move the cursor thru' the
hyperlink ENTER go to the selected hyperlink s apple Search for 'apple' inside
the text
-----------------------------------------------------------------------
Copy a file assigning permission to it Sintassi: install [options]
Options (see 'cp') : "-b" "--backup" "-S"
"--suffix" "-V" "--version-control" Options :
"-d < directory >" Create the specified dirs "-g
" Specify the owner group "-m
" Specify the permission "-o
" Specify the user who own the file
-----------------------------------------------------------------------
This install a Slackware Package Sintassi: installpkg [options] <
package_filename > "-warn" Don't perform the installation just
prompt what will happen "-r" Use current directory as root for
installing the package "-m" Make a package from the content of the
current directory
-----------------------------------------------------------------------
Display the list of jobs Sintassi: jobs [options] [job] Opzioni: -l
Display with PID -p Display only PID -n Display only the jobs that toggled
their fg/bg state
-----------------------------------------------------------------------
A usefull editor, also included in my "Little Italy Linux" It
accept command like the old Turbo Pascale editor Commands: CTRL + K + F
Search/Replace CTRL + K + S Save current file without quitting CTRL + C Quit
without to save, loosing chages CTRK + K + Z Quit saving if changed something
* K *
-----------------------------------------------------------------------
Change the keyboard mode. This program is only used to debug a new
keyboard layout. Please don't use them if you are not Linus Torvald.
-----------------------------------------------------------------------
One of the most famous program in the world, with "hallo world".
It's an old communication program thru' serial lines, we suggest to use 'minicom'
if you want test you internet connection.
-----------------------------------------------------------------------
kerneld is a 'daemon' that provide auto-load of modules. As example, if
you need PPP, kerneld will automatically load it when necessary without
running the modprobe or the insmod command. The behaviot of kerneld is
controlled by the file '/etc/conf.modules'
-----------------------------------------------------------------------
Send a "signal" to a process Sintassi: kill [options] [PID]
Opzioni: -s
Specify the name or number of the signal to send -l Display a list of all the
available signal Signals: 1) SIGHUP 2) SIGINT 3) SIGQUIT 4) SIGILL 5) SIGTRAP
6) SIGIOT 7) SIGBUS 8) SIGFPE 9) SIGKILL 10) SIGUSR1 11) SIGSEGV 12) SIGUSR2
13) SIGPIPE 14) SIGALRM 15) SIGTERM 17) SIGCHLD 18) SIGCONT 19) SIGSTOP 20)
SIGTSTP 21) SIGTTIN 22) SIGTTOU 23) SIGURG 24) SIGXCPU 25) SIGXFSZ 26)
SIGVTALRM 27) SIGPROF 28) SIGWINCH 29) SIGIO 30) SIGPWR
-----------------------------------------------------------------------
Send a signal to all the process who are executing a specified command
Sintassi: killall [options] [ -
] [
] -----------------------------------------------------------------------
Display log information about the "login" and the "logout"
from /var/log/wtmp of all the user or only from a single user Sintassi: last [options]
[user] Opzioni: -
or -n
Display only "number" events
-----------------------------------------------------------------------
Update the file /etc/ld.so.conf.cache and all the system libraries, also
add symlink to the right librarie version
-----------------------------------------------------------------------
Sintassi: lilo [options] -C < configuration file > Specify a
configuration file rather than /etc/lilo.conf -r
Specify a pseudo-root dir
-----------------------------------------------------------------------
This is the configuration file used by "lilo" It accept the
following options : boot=/dev/hda Specify on which partition or device will be
installed LILO. Don't user /dev/hda if you installed WindowNT as your default
system. prompt Tell LILO to dispay a prompt when it start timeout=50 Number of
1/10 seconds to wait before LILO exit from the prompt and load the default
image image=/boot/vmlinuz With this line start a definition of a Linux kernel
image to be loaded. Every line after this will be refered to this image. label=linux
Name to be used for the image at the LILO prompt root=/dev/hda2 Specify wich
partition must be mounted as root (i.e. /) for the specified image read-only
Needed if you are mounting an ext2fs partition other=/dev/hda1 With this line
start the definition of a image to be loaded of another OS. label=dos Tell the
label to use. table=/dev/hda ( I DON'T KNOW !)
-----------------------------------------------------------------------
Create a link (hard or symbolic) to one or more files or dirs Sintassi: ln
[options] source_file(s) target_file_or_dir Opzioni: "-n" ask before
overwrite an existing file with a link "-s" make a symbolic link
instead of an "hard link"
"-b" or --backup "-f" or --force "-i" or
--interactive "-S" or --suffix "-V" or --version-control
"-d" or "-F" or "--directory" Permit to create and
hard link to a directory "-n" or --no-dereference
-----------------------------------------------------------------------
Boot a Linux kernel from DOS Sintassi: Esempi: LOADLIN c:\vmlinuz root=/dev/hda2
ro Boot an ext2 partition on /dev/hda2 LOADLIN c:\vmlinuz root=/dev/hda1 rw Boot
an umsdos partition loadlinX c:\vmlinuz root=c: rw Boot an umsdos partition upon
C: -----------------------------------------------------------------------
Display/Set the LOCALE information (i.e. internetional settings) Sintassi: locale
[options] Opzioni: -a | --all-locale Show all the LOCALE name -m |
--charmaps Show all the avilable char maps
-----------------------------------------------------------------------
Logger let you add information to the system log Sintassi: logger [-f
file_to_include] [message] -----------------------------------------------------------------------
Output the name of the user you have used at login prompt, reading it from
/var/run/utmp To know which user are you currently using use 'whoami' instead.
-----------------------------------------------------------------------
Print a file Sintassi: lp [-c] [-d < printer >] [-m] [-n <
copies >] [-o < print_options > ] [-P < page_to_be_printed >]
[-w] < file_to_print > Opzioni: "-c" make a copy of the file
to be printed "-d" specifies an output printer "-m" send a
mail message when the print job is completed "-n" number of copies to
print "-o" specifies print Opzioni: nobanner, nofilebreak, cpi=
lpi=
, lenght=
i, lenght=
l, width=
width=
i "-P" specifies which pages have to be printed "-w" display
a message on the screen when the print job is completed
-----------------------------------------------------------------------
List the files present into a directory Sintassi: ls [options]
Opzioni: "-l" display info into a "long" format
"-a" display all the files including hidden files "-A" like
"-a" but does not show the "." and ".." directory
(VERY USEFULL) "-q" Change non-printable chars with the "?"
symbol "-R" Recurse thru' subdirectories "-t" Sort the
result starting from the most recent modify-date "-c" Sort the result
starting from the most recent change-date "-u" Sort the result
starting from the most recent access-date "-e" Display full date time
for the files. "-i" Show inode "-r" Sort in reverse order
"-B" Ignore backup files (~) "-C" Use a vertical format
organized in columns "-F" Apped a char at the end of a file, depending
on its type: * program; / directory; @ symlink; | pipe; = socket "-S"
Sort by size "-X" Sort by extension "-1" format using a
single column, one file per line "-w
" Set the width of the ouput, used if you have a screen more than 80 chars
or less "-I
" Exclude listing of the specified patterns
-----------------------------------------------------------------------
Show the attribute of a file on an ext2 file system Sintassi: lsattr [options]
< files > Opzioni: "-R" Recurse thru' subdirs "-a"
All files, including hidden "-d" Also list subdirs
-----------------------------------------------------------------------
List all the modules loaded into the kernel Sintassi: rmmod [-r] [module_name]
If the -r parameter is specified then rmmod try to 'recursively' remove all
unneeded modules depending on the specified once.
-----------------------------------------------------------------------
* M *
-----------------------------------------------------------------------
The second most know program by programmers :-) Make is used to execute
makefiles that usually automate the process of compiling your software project
-----------------------------------------------------------------------
The manpages viewer Sintassi: man [options] [name] Opzioni:
A section number is between 1 and 9, see manpages below -f Act like 'whatis' -h
Show guide -k Act like 'apropos'
-----------------------------------------------------------------------
manpages are usually stored into /usr/share/man , dependly on their
extension they handle different topics, depending on their category: 1 user
command 2 syscall 3 library function 4 devices 5 file formats 6 games 7 misc 8
system commands 9 kernel routine
-----------------------------------------------------------------------
The famous "Midnight Commander", a clone of the Norton Commander
dos program. This is included by default into my "Little Italy Linux"
-----------------------------------------------------------------------
mgetty is the daemon that allow you to login onto your system. Its a very
complex program. Sintassi: mgetty [options] < linea-tty > Opzioni:
"-x
" Verbose Level from 0 (none) to 9 "-s
" Port speed "-r" Use a serial line with no modem "-p
" Customize the login prompt "-i
" Use a custom issue file instead of /etc/issue Examples: mgetty -r -s
19200 ttyS1 mgetty -r -x 9 -s 19200 ttyS1
-----------------------------------------------------------------------
Enable/disable the display of messages on the screen using the comamnd
"write" Sintassi: mesg [y|n] -----------------------------------------------------------------------
A small version of getty with no modem or serial line support to reduce
memory use. Do not use any configuration file. Sintassi: mingetty [options] [virtual
console] Opzioni: --noclear Do not clear the screen before the login
--long-hostname Display the complete computer name at the login prompt Esempi:
mingetty tty1
-----------------------------------------------------------------------
Create one or more directories Sintassi: mkdir [options] < directory
> ... Opzions: "-m | --mode=
" Define permission "-p | --parents" Create the full-tree of
parent dirs not only the target child "--verbose" Verbose
-----------------------------------------------------------------------
Make an ext2 file system on the specified device Syntax for ext2 fs : mke2fs
[options] < device > [dimension in blocks] Syntax for dos fs : mkedos
[options] < device > [dimension in blocks] General Syntax : mkfs [
-t < fs type > ] [options] < device > [dimension in blocks] Opzioni:
"-b < block size >" "-c" Check badblocks "-i
" "-q" Silent "-S" Write only the superbock (Latest
recover resource)
-----------------------------------------------------------------------
Make a ISO-9660 filesystem (cd-rom) image from the specified directory
Sintassi: mkisofs [options] < directory > Opzioni: "-a"
Include all files "-f" Symlinks are converted into the pointed files
"-m < model >" Exclude all the files or dirs that are present
into the model "-o < file >" Specify the output file for the
image "-R" Add the Rock-Ridge extensions "-r" Adjust
permission for the file into the ISOfs "-T" Enable the creation of
files TRANS.TBL into every directory "-v" Verbose "-x <
directory >" Exclude that directory
-----------------------------------------------------------------------
Create a FIFO or a special device file. Sintassi: mknod [options] <
file >
[ < major nr. > < minor nr. > ] Tyep: "p" Create a
FIFO "b" Create a block buffered device "c" Create a char
buffered device "u" Create a char unbuffered device Opzioni: -m [
| --mode=[
] Set permission
-----------------------------------------------------------------------
modprobe is used instead of 'insmod' because it use 'modules.dep' to find
the dependencies the module need. In this way modprobe load all the needed
modules while insmod load only the specified modules. Sintassi: modprobe [options]
[module_name] [module_parameters] Opzioni: -a Load all the modules -c Show
the current configuration -l List all the available modules -r Remove all loaded
modules -----------------------------------------------------------------------
Display the standard input one page at time on the screen Sintassi: more
[options] [file] Esempi: cat /etc/passwd | more more /etc/passwd Keyboard
Shortcuts q Quit the program h Show the on-line help SPACE Show the next page
ENTER Show the next line b Show the previous page /apple Search the text for 'apple'
n Find the text again CTRL+l Refresh the current screen The 'less' command,
additionally can use the arrow and page key to scroll the text also if it cames
from the standard input. Also it have this additional shortcut: y Show the
previous line ?apple Search backward for 'apple' N Repeat last backward search
-----------------------------------------------------------------------
Mount the filesystem from a device into a directory (the mount point).
Sintassi: mount [ -t < fs_type>] [-o ro|rw] < device_name > <
mount_point > Esempi: mount -t vfat /dev/fd0 /floppy mount the windoze
floppy a: under /floppy mount -t iso9660 /dev/scd0 /cdrom mount your scsi cdrom
under /cdrom mount -a mount all the filsystems into /etc/fstab mount -a -t
nomsdos,nonfs mount all the filsystems into /etc/fstab execpt the once that are
of type msdos and nfs Opzioni: "-a" Mount all the FS into /etc/fstab
execpt the once makerd with 'noauto' "-t < FS-type > Specify the FS
type "-o < FS-Option > Specify "rw" or "ro" to
mount the fs read/write or read/only
-----------------------------------------------------------------------
Move files or directory, also rename, because rename is just as moving into
the same directory Sintassi: mv [options] < source > < target > Opzioni:
-b | --backup -f | --force -i | --interactive -S | --suffix -V |
--version-control
-----------------------------------------------------------------------
Run a command at a specified priority ( "nice" ) Sintassi: nice
[options] [command] [arguments] Opzioni: -n < nice > Assign a priority
from -20 (higher) to +19 (lowest)
-----------------------------------------------------------------------
Run a command in a way that it cannot be interrupted with the signal (SIGHUP)
Esempi: nohup yes > /dev/null &
-----------------------------------------------------------------------
open let you start a command upon a new virtual console Sintassi: open [options]
[--] < command > [command options] Opzioni: -c < console number
> Specify a virtual console to use -l Treath the command as a login shell
Change your password or the once of a specified user Sintassi: passwd [options]
[username] Opzioni: "-s" view status information
-----------------------------------------------------------------------
Apply a patch to one or more files. The patch is usually created with the 'diff'
command -----------------------------------------------------------------------
This is not the MAIL daemon ! Its a utility to get-off from the directory
stack an item pushed with "pushd". Sintassi: popd [+/-n] -----------------------------------------------------------------------
Display information about the processes currently running on the system
Sintassi: ps [-l] [-a] [-e] [-f] [-t
] [-u < user_names >] "-l" display with long format
"-f" display the process dependencies (see pstree) "-a",
"-e" display all process "-t" view process started from that
terminal "-u" view process started from that user "-x" view
process that run in background "-r" view only the running process
"-h" strip the header from the ps list
-----------------------------------------------------------------------
Display running process with a graphical tree Sintassi: pstree [options]
[ PID | user ] Opzioni: "-a" Show the command-line "-p"
Show the PIDs "-u" Show UUID transaction Esempi: ps -u -p
-----------------------------------------------------------------------
Add a directory on the top of the directory stack Sintassi: pushd [<
directory >] | pushd [+/-n] -----------------------------------------------------------------------
pwck check the integrity of the file /etc/passwd and /etc/shadow Sintassi:
pwck [-r] [ < passwd-file > [shadow-file]] Opzioni: "-r"
read-only check, do not fix anything
-----------------------------------------------------------------------
Convert your /etc/passwd into /etc/passwd and /etc/shadow. Password are
removed from the /etc/passwd file. If /etc/shadow already exist it is simply
updated. This program does not get any parameters, any default value is taken
from /etc/login.defs
-----------------------------------------------------------------------
pwd (Print Working Directory) output the name of the current directory
Sintassi: pwd [options] -----------------------------------------------------------------------
pwunconv make the reverse work of "pwconv". It convert /etc/shadow
into /etc/passwd then erase it.
-----------------------------------------------------------------------
The quotha manager, handle the amount of space a user can consume upon a
system Sintassi: quota [ options ] Opzioni: -u [ user ] Get the quotas
for the specified user -g [ group ] Get the quotas for the specified group
Examples: quota Get the quota for the current user
-----------------------------------------------------------------------
Scan all the partition to update the files quota.user and quota.group, its
good to do this at boot time Sintassi: quotacheck [ options ] [{<
partition >|< mount-point >}...] Opzioni: -u Scan user quota (default)
-g Scan group quota -a Scan all the partition into /etc/fstab -R Scan all the
partition into /etc/fstab except "/" (root) Examples: quotacheck /dev/hdb2
quotacheck /mnt/disco2 quotacheck -avug
-----------------------------------------------------------------------
Enable quota manager Sintassi: quotaon [ options ] [{< partition
>|< mount-point >}...] Opzioni: -u Enable user quota -g Enable
group quota -a Enbale quota according to /etc/fstab Examples: quotaon /dev/hdb2
quotaon /mnt/disco2 quotaon -avug Questo corrisponde all'utilizzo normale del
programma, per attivare la gestione delle quote in tutte le partizioni montate e
registrate nel file /mnt/disco2 come soggette al controllo delle quote, sia
degli utenti che dei gruppi.
-----------------------------------------------------------------------
Utility to set parameters into a kernel image Sintassi:
Esempi: rdev kernel_image device_name Specify a new root device rdev -R
kernel_image 1 Specify to mount the root filesystem as read only rdev -R
kernel_image 1 Specify to mount the root filesystem as read/write rdev -s
kernel_image device_name Specify to use a default swap file rdev /dev/fd0 /dev/hdb1
Configure the image upon a floppy to mount the rootFS from the first partition
onto the secondary EIDE disk
-----------------------------------------------------------------------
Bash command to read a string from standard input Sintassi: read [-a <
array > ] [-p < prompt > ] [-r] [ < variabile >... ] Opzioni:
-r Parse "\" as a valid char -a < array > Fill a specified array
with the parsed values -p < prompt > Output a prompt
-----------------------------------------------------------------------
Deinstall a Slackware Package Sintassi: removepkg [-warn] <
package_name > Opzioni: "-warn" do not really remove the
package only warn
-----------------------------------------------------------------------
Run a command at a specified priority ( "nice" ) Sintassi: renice
[ [-p]
... ] [ [-g]
... ] [ [-u]
... ] Opzioni: -g
Specify a group PID (PGRP) -u user Specify a user name -p
Specify a PID
-----------------------------------------------------------------------
Reset the terminal if a lot of strange characters appear on your screen.
Sometimes this is a shell script.
-----------------------------------------------------------------------
Remove one or more file or an entire directory tree Sintassi: rm [option]
< target > Opzioni: -r | -R | --recursive Recursively delete file into
a directory -i | --interactive Ask before to remove -d | --directory Threat
directories as files -f | --force Ovverride the -i parameters and delete without
asking any confirmation
-----------------------------------------------------------------------
Erase any specified directory Sintassi: rmdir [ options ] < directory
>... Opzioni: -p | --parents Erase also the parent directory if it is
empty -----------------------------------------------------------------------
Remove a module from the kernel Sintassi: rmmod [-r] [module_name] If
the -r parameter is specified then rmmod try to 'recursively' remove all
unneeded modules depending on the specified once.
-----------------------------------------------------------------------
RedHat Package Manager, it install, deinstall, upgrade, etc., every RedHat
package Syntax (user rpm --help to gain the full help): RPM version 2.3.10
Copyright (C) 1997 - Red Hat Software This may be freely redistributed under the
terms of the GNU Public License usage: --help - print this message --version -
print the version of rpm being used -q - query mode --root < dir > - use
< dir > as the top level directory --dbpath < dir > - use < dir
> as the directory for the database install, upgrade and query (with -p)
allow ftp URL's to be used in place of file names as well as the following
Opzioni: Package specification Opzioni: -a - query all packages -f < file
>+ - query package owning < file > -p
+ - query (uninstalled) package
--whatprovides < i > - query packages which provide < i >
capability --whatrequires < i > - query packages which require < i >
capability Information selection Opzioni: -i - display package information -l -
display package file list -s - show file states (implies -l) -d - list only
documentation files (implies -l) -c - list only configuration files (implies -l)
--dump - show all verifiable information for each file (must be used with -l,
-c, or -d) --provides - list capabilities package provides --requires -R - list
package dependencies --scripts - print the various [un]install scripts -V -y
--pipe
- send stdout to
--verify - verify a package installation using the same package specification
options as -q --dbpath < dir > - use < dir > as the directory for
the database --root < dir > - use < dir > as the top level directory
--nodeps - do not verify package dependencies --nomd5 - do not verify file md5
checksums --nofiles - do not verify file attributes --setperms - set the file
permissions to those in the package database using the same package
specification options as -q --setugids - set the file owner and group to those
in the package database using the same package specification options as -q
--install
-i
- install package --prefix < dir > - relocate the package to < dir
>, if relocatable --dbpath < dir > - use < dir > as the directory
for the database --excludedocs - do not install documentation --force - short
hand for --replacepkgs --replacefiles -h --hash - print hash marks as package
installs (good with -v) --ignorearch - don't verify package architecture
--ignoreos - don't verify package operating system --includedocs - install
documentation --nodeps - do not verify package dependencies --noscripts - don't
execute any installation scripts --percent - print percentages as package
installs --replacefiles - install even if the package replaces installed files
--replacepkgs - reinstall if the package is already present --root < dir >
- use < dir > as the top level directory --test - don't install, but tell
if it would work or not --upgrade
-U
- upgrade package (same options as --install, plus) --oldpackage - upgrade to
an old version of the package (--force on upgrades does this automatically)
--erase
-e
- erase (uninstall) package --allmatches - remove all packages which match
(normally an error is generated if
specified multiple packages) --dbpath < dir > - use < dir > as the
directory for the database --nodeps - do not verify package dependencies
--noscripts - do not execute any package specific scripts --root < dir > -
use < dir > as the top level directory -b
-t
- build package, where
is one of: p - prep (unpack sources and apply patches) l - list check (do some
cursory checks on %files) c - compile (prep and compile) i - install (prep,
compile, install) b - binary package (prep, compile, install, package) a - bin/src
package (prep, compile, install, package) --short-circuit - skip straight to
specified stage (only for c,i) --clean - remove build tree when done --sign -
generate PGP signature --buildroot < s > - use s as the build root --test
- do not execute any stages --timecheck < s > - set the time check to S
seconds (0 disables it) --rebuild
- install source package, build binary package and remove spec file, sources,
patches, and icons. --recompile
- like --rebuild, but don't build any package --resign
+ - sign a package (discard current signature) --addsign
+ - add a signature to a package -K --checksig
+ - verify package signature --nopgp - skip any PGP signatures --nomd5 - skip
any MD5 signatures --querytags - list the tags that can be used in a query
format --initdb - make sure a valid database exists --rebuilddb - rebuild
database from existing database --dbpath < dir > - use < dir > as
the directory for the database --root < dir > - use < dir > as the
top level directory -----------------------------------------------------------------------
Save into a text file every command you issue from the keyboard. Very
usefull for making shell script Sintassi: script [-a] < file > Opzioni:
"-a" Append the typed command to a pre-existing script file rather
than creating a new one To quit the recording use the 'exit' command.
-----------------------------------------------------------------------
Used to set some 'bash' behavious Sintassi: set [flag] [
... ] Flags: -a Automatically export any modified or create vars to the
shell -b Immediately report the status of a teminated background job -e
Immediately quit if a command return a value not zero This not work if the
command is inside of a while loop, an if statement, a list
"&&" o "||" or if the command was inverted with
"!" -f Disable file/path globbing -h Store into a cache the position
of each executable file that is run -k Export to any sub-command every local
variable -m Enable Job control -n Read command without execute (used to perform
syntax checks) -o
shift
Shift the program parameters of "n" positions except $0 Sintassi:
shift [n] -----------------------------------------------------------------------
Configuration file for syslinux Opzioni: DEFAULT linux Tell to use "linux"
as default label TIMEOUT 50 Specify how many 1/10 of seconds to wait to start
the default kernel To wait forever specify 0 (zero) DISPLAY INTRO.TXT Display
the content of the file INTRO.TXT PROMPT 1 Ask user for something. Set to 0 to
override this F1 INTRO.TXT Set the F1 key to display this text, and so on for
F2, F3, ecc. LABEL linux Define a label KERNEL LINUX Specify which kernel image
to load for the last labeò LABEL floppy Special label to tell to insert a new
floppy with a compressed root partition ramdisk image LABEL hda1 Tell to start
with the kernel on /dev/hda1
-----------------------------------------------------------------------
Load a specified font file, or the default if nothing is specified Sintassi:
setfont [ options ] < font-file > -----------------------------------------------------------------------
Change the keyboard's led state Sintassi: setleds [options] [[+|-]num]
[[+|-]caps] [[+|-]scroll] Opzioni: "" If you run the program with
no options you will get the current settings "-D" Settings are stored
so a 'reset' command will not change them "-L" Change only the led
status but not his meanings.
-----------------------------------------------------------------------
Display the keycode for every key you press. The program quit after 10
seconds of inactivity. Sintassi:showkey [ options ]
-----------------------------------------------------------------------
Halt or reboot a machine Sintassi: Opzioni: "-h" halt the machine
"-r" reboot the machine
-----------------------------------------------------------------------
*Signal* *Action* *Description* SIGHUP A The Terminal hang-up (lost
connection). SIGINT A Program Interrupted (usually CTRL+C) SIGQUIT A Program
Quitted. SIGILL A Illegal Instruction. SIGABRT C Program aborted (interruped by
the system). SIGFPE C Floating Point Exception. SIGKILL AEF Process Killed.
SIGSEGV C Segmentation Fault (You have problem with your system). SIGPIPE A
Broken Pipe. SIGALRM A Timer Alarm. SIGTERM A Program Terminated (maybe with
KILL -TERM ...). SIGUSR1 A User Signal 1. SIGUSR2 A User Signal 2. SIGCHLD B A
child process is quit. SIGCONT If stopped, restart the execution. SIGTSTOP DEF
Immediatly stop the process. SIGTSTP D Stop signal from a keyboard command.
SIGTTIN D Background process who need input. SIGTTOU D Background process who
need output. *Actions* A process is quitted; B signal ignored; C make a
"core" dump; D process is stopped; E process cannot be catched; F
process cannot be ignored.
-----------------------------------------------------------------------
Change settings of the terminal Sintassi:stty [options | <
configuration >] Opzioni: "-a" Show the current configuration
-----------------------------------------------------------------------
Let you login as another user without exiting from your current console
session. If no user is specified the 'root' user is used as default. Sintassi:su
[ options ] [ user ] -----------------------------------------------------------------------
Enable the use of a swap partition or file Sintassi:swapon [ options ] [
device ] Opzioni: "-a" Enable all the swap partition defined into
/etc/fstab Examples: # swapon /dev/hda3 Enable the swap partition /dev/hda3. #
swapon /swap1 Enable the swap file /swap1. # swapon -a Enable the swap partition
specified into /etc/fstab, if any.
-----------------------------------------------------------------------
switchto is used to switch the screen to another virtual console without
pressing any key Sintassi: switchto [virtual console number] -----------------------------------------------------------------------
sync perform the flush of the file cache buffer, writing pending information
to the disk Sintassi: sync [ options ] -----------------------------------------------------------------------
syslogd is the daemon that take care of booking every system event. It's
configuration file is /etc/syslogd.conf Sintassi: syslogd [ options ] Options
: -f < configuration file > -m < minutes > -p
-----------------------------------------------------------------------
SVGATextMode is used to resize the console size at any time. Its
configuration file is /etc/TextConfig Sintassi: SVGATextMode[ options ] [configuration
voice] -----------------------------------------------------------------------
* T *
-----------------------------------------------------------------------
Display a file in reverse order, from the bottom to the top. tac works as
the opposite of cat. See cat for command options. Sintassi: tac [ options ]
[file... ] -----------------------------------------------------------------------
Display the last lines of a file Sintassi:tail [-r] [-
] < file_name > Opzioni: "-r" view in reverse order
-----------------------------------------------------------------------
tar (Tape ARchive) manage archive files Sintassi: tar [c|r|t|u|x|A][options][f
< tar_file >] < file_names > Opzioni: "c" copy on a
new file or floppy "r" copy at the end of a pre-existing archive
"t" view files inside of an archive "u" Update archive with
only new files "-A" Append files to a pre-existing archive
"-d" Find difference between the files into the archive and the
filesystem "--delete" Delete from an archive all the specified files
"x" extract files from the archive "l" display an error
message if the desidere file is not found "o" when extracting a file
use the current user attributes instead of the orginal file owner "v"
view name of the file being processed "w" ask before to copy any file
"0-9" device number "f" specify the archive file name
"-r" o "--append" Aggiunge dati a un archivio già
esistente. "-t" o "--list" Elenca il contenuto di un
archivio. "-u" o "--update" Aggiunge solo i file più
recenti rispetto a quanto già contenuto nell'archivio. "-x" o "--extract"
Estrae i file da un archivio. "--atime-preserve" Fa in modo che la
data di accesso dei file che vengono archiviati, non venga modificata. "-f
< file >" Emette l'archivio nel file o nel device. Se si tratta di un
file normale, questo viene creato. "-h" o "--dereference"
Non copia i link simbolici, ma i file a cui questi fanno riferimento.
"-k" o "--keep-old-files" In fase di estrazione da un
archivio, non sovrascrive i file eventualmente già esistenti. "-l" o
"--one-file-system" Quando viene creato un archivio, resta in un solo
filesystem: quello di partenza. "-L
" o "--tape-length=
" Definisce la dimensione massima dei vari segmenti di copia multivolume.
"-m" o "--modification-time" In fase di estrazione da un
archivio, non viene ripristinata la data di modifica dei file. "-M" o
"--multi-volume" Permette di creare, elencare o estrarre un archivio
multivolume. "-N
" o "--newer
" Archivia solo i file la cui data è più recente di quella indicata come
argument. "-O" Estrae i file nello standard output. "-p" o
"--preserve-permissions" Estrae tutti i permessi associati ai file.
"-P" o "--absolute-path" Estrae i file utilizzando i
percorsi assoluti, cioè senza eliminare la prima barra (/) che appare nei nomi
di percorso (pathname). "--remove-files" In fase di creazione di un
nuovo archivio, elimina i file archiviati. "--same-owner" Durante
l'estrazione da un archivio, assegna ai file estratti le proprietà originali.
"-v" o "--verbose" Elenca i file che vengono elaborati.
"-W" o "--verify" Cerca di verificare la validità
dell'archivio dopo averlo creato. "-Z" Filtra l'archivio attraverso il
programma di compressione compress. "-z" Filtra l'archivio attraverso
il programma di compressione gzip. Esempi: # tar -c -f /dev/fd0 -L 1440 -M -v /usr
Archivia la directory /usr/ con tutto il suo contenuto, comprese le
sottodirectory, utilizzando i dischetti (da 1440KB). Con la copia multivolume,
come in questo caso, non è possibile utilizzare la compressione automatica
attraverso l'opzione -z o -Z. # tar -t -f /dev/fd0 -L 1440 -M -v Visualizza
l'elenco del contenuto dell'archivio fatto su dischetti. # tar -x -f /dev/fd0 -L
1440 -M -v -p --same-owner Estrae il contenuto dell'archivio su dischetti a
partire dalla posizione corrente. È probabile che le options -p e --same-owner
siano già predefinite a causa di una opportuna modifica fatta da chi ha
realizzato la distribuzione Linux. In ogni caso vale la pena di ricordarsene. #
tar -c -f /tmp/archivio.tgz -z -v /usr Archivia il contenuto della directory /usr/
nel file /tmp/archivio.tgz dopo averlo compresso con gzip
-----------------------------------------------------------------------
Copy text between a pipe and a file Sintassi: tee [-a] file_names Opzioni:
"-a" append to the existing file instead of overwrite Exampe: find .
-atime +30 | tess file.old.txt
-----------------------------------------------------------------------
test is used in shell script to evaluate a condition. It return 0 for TRUE
or 1 for FALSE Sintassi: test < condition > Conditions: -e <
file > File exist -b < file > File is a block device -c < file >
File is a char device -d < file > File is a directory -f < file >
File is normal -L < file > File is a symlink -p < file > File is a
named-pipe -S < file > File is a socket -t [
] File descriptor is open on the terminal -g < file > File has SGID bit
set -u < file > File has SUID bit set -k < file > File has "sticky"
bit set -r < file > File is readable -w < file > File is writable -x
< file > File can be executed -O < file > File is owned by the
current user UID -G < file > File is owned by the current user group GID
-s < file > Filesize is greater than 0
-nt
First file is newer than second
-ot
First file is older thant second
-et
Files are the same (hard-link) -z
String is NULL -n
String is not NULL
==
Strings are equal
!=
Strings are different
<
First string come first
>
Second string come first -eq Equals -ne Different -lt Lower than -le Lower or
equal of -gt Greater than -ge Greater or equal of !
Negation
-a
AND
-o
OR -----------------------------------------------------------------------
Display the list of the system process and also let you manage them
interactively Sintassi: top [options] Opzioni: -d
Delay in seconds between updates -s Disable some commands, this is used to let
top stay on a separated tty -i View "zombie" process -c View the
command-line instad of only the command name Commands: q Quit top h Show top
commands -----------------------------------------------------------------------
Cambia la data-ora di accesso e di aggiornamento dei file. Se non viene
specificata una data, viene utilizzata la data nel momento in cui viene eseguito
il comando. Se il file specificato non esistone, allora viene crato vuoto.
Sintassi: touch [-a] [-c] [-m] [date] < files_name > Opzioni:
"-a" Viene cambiata solo la data di accesso. "-c" Non
vengono creati i file che non esistono. "-m" Cambia solo la data di
aggiornamento. "-r
" Riproduce gli stessi dati del file indicato. "-t
[[
]
[.
]]" Usa la data in argomento invece della data corrente.
-----------------------------------------------------------------------
"trap" a signal executing a command when this happen Sintassi: trap
[-l] [command] [signal] Esempi: $ trap 'ls -l' SIGUSR1 Se la shell riceve un
segnale SIGUSR1 esegue ls -l. $ trap '' SIGUSR1 La shell e tutti i processi
figli ignorano il segnale SIGUSR1. $ trap - Tutti i segnali specificati sono
riportati al loro valore originale $ trap 'echo "bye." EXIT Il comando
viene eseguito all'uscita della shell quando il segnale e' EXIT
-----------------------------------------------------------------------
Permette di controllare le risorse disponibili dalla shell ed i suoi
processi. Sintassi: ulimit [ options ] [ limite ] Opzioni: "-H"
Imposta il limite hard per la data risorsa. "-S" Imposta il limite
soft per la data risorsa. "-a" Sono riportati tutti i limiti correnti.
"-c" La grandezza massima dei file core creati. "-d" La
grandezza massima del segmento dati di un processo. "-f" La grandezza
massima dei file creati dalla shell. "-m" La grandezza massima della
memoria occupata. "-s" La grandezza massima dello stack.
"-t" Il massimo quantitativo di tempo di CPU in secondi.
"-p" La grandezza della pipe in blocchi da 512 byte "-n" Il
numero massimo di descrittori di file aperti "-u" Il numero massimo di
processi disponibili per un singolo user. "-v" Il massimo ammontare di
memoria virtuale disponibile per la shell.
-----------------------------------------------------------------------
Modifica la maschera di creazione dei file dell'user. Di solito si usa il
valore 022 Sintassi: umask [-S] [ modalità ] Opzioni: "-S"
viene emesso il valore corrente della maschera
-----------------------------------------------------------------------
Smonta i filesystems Sintassi: umount [ options ] [ device ] [ directory
] Esempi: umount /floppy Dismount the FS mounted under /floppy umount /dev/fd0
Dismount the floppy Opzioni: "-a" Vengono smontati tutti i filesystem
indicati in /etc/fstab. "-t [no]
[,...]" Indica che l'azione deve essere eseguita solo sui filesystem
specificati. Se si usa il prefisso no, l'azione si deve compiere su tutti i
filesystem a esclusione di quelli indicati.
-----------------------------------------------------------------------
Rimuove l'alias indicato dalla lista degli alias definiti. Se viene fornita
l'opzione -a, sono rimosse tutte le definizioni di alias. Sintassi: unalias
[-a] [nome-di-alias ... ] -----------------------------------------------------------------------
Tell wich system you are running Sintassi: uname [-s] [-a] "-s"
view only the system name "-a" view more
-----------------------------------------------------------------------
Decompress a ".Z" file Sintassi: uncompress [-c]
"-c" view the compressed files without converting it
-----------------------------------------------------------------------
Tell from how many time a system is ON ... this can be a value of different
years. -----------------------------------------------------------------------
Con questo nome, update, viene avviato il daemon che si occupa di richiedere
periodicamente al kernel lo scarico della memoria cache. Sintassi: update [
options ] -----------------------------------------------------------------------
Il programma useradd permette di aggiungere un nuovo utente in un sistema in
cui siano attive, o meno, le password shadow. Sintassi: useradd -D [ options
] -----------------------------------------------------------------------
userdel permette di eliminare un account utente Sintassi: userdel [-r]
user "-r" elimina anche la directory home dell'user eliminato
-----------------------------------------------------------------------
Permette di modificare alcune caratteristiche di un account utente.
Sintassi: usermod [ options ] user -----------------------------------------------------------------------
uugetty si comporta in modo analogo a getty (con la stessa sintassi e le
stesse options), con la differenza fondamentale che utilizza lo stesso sistema
di file di lock usati dai programmi uucp. In pratica uugetty viene usato tutte
le volte che entra in gioco il modem. Sintassi: uugetty [ options ]
[
[
] ] -----------------------------------------------------------------------
* V *
-----------------------------------------------------------------------
Visualizza i nomi degli utenti che accedono attualmente e varie informazioni
sulla loro attività.
-----------------------------------------------------------------------
Attende la conclusione del processo specificato e restituisce il suo stato
di uscita. Sintassi: wait [n] -----------------------------------------------------------------------
Search into the 'whatis' database, that contain info about the command
system, for one or more words. The 'whatis' database is generated thru' the
command 'makewhatis'
-----------------------------------------------------------------------
Localizza i file binari, i sorgenti e le pagine di manuale dei file
specificati nell'argument. Sintassi: whereis [ options ] < file > -----------------------------------------------------------------------
Simula la ricerca che farebbe la shell per avviare i programmi indicati
negli argomenti e determina la posizione di quelli che verrebbero scelti.
Sintassi: which
... -----------------------------------------------------------------------
Visualizza il nome dell'account utente che si sta' utilizzando. E'
equivalente a id -un.
-----------------------------------------------------------------------
A strange program used for testing, it print continuosly a letter
"y" on a new line. Use CTRL+C or the kill command to stop it
-----------------------------------------------------------------------
zcat come programma autonomo non esiste: è un link a gzip. Se gzip viene
avviato con il nome zcat si comporta come se fosse stata utilizzata l'opzione
-c. Il link verso gzip può essere sia simbolico che non.
-----------------------------------------------------------------------