|
Command |
Description |
|
• |
apropos whatis |
Show
commands pertinent to string. See also
threadsafe |
|
• |
man -t man
| ps2pdf - > man.pdf |
make a pdf of
a manual page |
|
|
which command |
Show full path
name of command |
|
|
time command |
See how long a
command takes |
|
• |
time cat |
Start
stopwatch. Ctrl-d to stop. See also
sw |
|
dir
navigation |
|
• |
cd - |
Go to previous
directory |
|
• |
cd |
Go to $HOME
directory |
|
|
(cd dir &&
command) |
Go to dir,
execute command and return to current dir |
|
• |
pushd
. |
Put current
dir on stack so you can popd back to it |
|
file searching |
|
• |
alias l='ls
-l --color=auto' |
quick dir
listing |
|
• |
ls -lrt |
List
files by date. See also
newest and
find_mm_yyyy |
|
• |
ls /usr/bin |
pr -T9 -W$COLUMNS |
Print in 9
columns to width of terminal |
|
|
find -name
'*.[ch]' | xargs grep -E 'expr' |
Search 'expr'
in this dir and below. See also
findrepo |
|
|
find -type f
-print0 | xargs -r0 grep -F 'example' |
Search all
regular files for 'example' in this dir and below |
|
|
find -maxdepth
1 -type f | xargs grep -F 'example' |
Search all
regular files for 'example' in this dir |
|
|
find -maxdepth
1 -type d | while
read dir; do echo $dir; echo cmd2; done |
Process each
item with multiple commands (in while loop) |
|
• |
find -type f !
-perm -444 |
Find files not
readable by all (useful for web site) |
|
• |
find -type d !
-perm -111 |
Find dirs not
accessible by all (useful for web site) |
|
• |
locate -r
'file[^/]*\.txt' |
Search cached
index for names. This re is like glob *file*.txt |
|
• |
look reference |
Quickly search
(sorted) dictionary for prefix |
|
• |
grep
--color reference /usr/share/dict/words |
Highlight
occurances of regular expression in dictionary |
|
archives and
compression |
|
|
gpg -c file |
Encrypt file |
|
|
gpg file.gpg |
Decrypt file |
|
|
tar -c dir/ |
bzip2 > dir.tar.bz2 |
Make
compressed archive of dir/ |
|
|
bzip2 -dc
dir.tar.bz2 | tar -x |
Extract
archive (use gzip instead of bzip2 for tar.gz files) |
|
|
tar -c dir/ |
gzip | gpg -c | ssh user@remote 'dd of=dir.tar.gz.gpg' |
Make encrypted
archive of dir/ on remote machine |
|
|
find dir/
-name '*.txt' | tar -c --files-from=- | bzip2 >
dir_txt.tar.bz2 |
Make archive
of subset of dir/ and below |
|
|
find dir/
-name '*.txt' | xargs cp -a --target-directory=dir_txt/
--parents |
Make copy of
subset of dir/ and below |
|
|
( tar -c /dir/to/copy
) | ( cd /where/to/ && tar -x -p ) |
Copy (with
permissions) copy/ dir to /where/to/ dir |
|
|
( cd /dir/to/copy
&& tar -c . ) | ( cd /where/to/ && tar -x -p
) |
Copy (with
permissions) contents of copy/ dir to /where/to/ |
|
|
( tar -c /dir/to/copy
) | ssh -C user@remote 'cd /where/to/ && tar -x -p'
|
Copy (with
permissions) copy/ dir to remote:/where/to/ dir |
|
|
dd bs=1M if=/dev/sda
| gzip | ssh user@remote 'dd of=sda.gz' |
Backup
harddisk to remote machine |
|
rsync
(Network efficient file copier: Use the --dry-run
option for testing) |
|
|
rsync -P rsync://rsync.server.com/path/to/file
file |
Only get diffs.
Do multiple times for troublesome downloads |
|
|
rsync
--bwlimit=1000 fromfile tofile |
Locally copy
with rate limit. It's like nice for I/O |
|
|
rsync -az -e
ssh --delete ~/public_html/ remote.com:'~/public_html' |
Mirror web
site (using compression and encryption) |
|
|
rsync -auz -e
ssh remote:/dir/ . && rsync -auz -e ssh .
remote:/dir/ |
Synchronize
current directory with remote one |
|
ssh
(Secure SHell) |
|
|
ssh $USER@$HOST
command |
Run command on
$HOST as $USER (default command=shell) |
|
• |
ssh -f -Y
$USER@$HOSTNAME xeyes |
Run GUI
command on $HOSTNAME as $USER |
|
|
scp -p -r
$USER@$HOST: file dir/ |
Copy with
permissions to $USER's home directory on $HOST |
|
|
ssh -g -L
8080:localhost:80 root@$HOST |
Forward
connections to $HOSTNAME:8080 out to $HOST:80 |
|
|
ssh -R 1434:imap:143
root@$HOST |
Forward
connections from $HOST:1434 in to imap:143 |
|
|
ssh-copy-id
$USER@$HOST |
Install
$USER's public key on $HOST for password-less log in |
|
wget
(multi purpose download tool) |
|
• |
(cd dir/ &&
wget -nd -pHEKk http://www.pixelbeat.org/cmdline.html) |
Store local
browsable version of a page to the current dir |
|
|
wget -c
http://www.example.com/large.file |
Continue
downloading a partially downloaded file |
|
|
wget -r -nd
-np -l1 -A '*.jpg' http://www.example.com/dir/ |
Download a set
of files to the current directory |
|
|
wget
ftp://remote/file[1-9].iso/ |
FTP supports
globbing directly |
|
• |
wget -q -O-
http://www.pixelbeat.org/timeline.html | grep 'a
href' | head |
Process output
directly |
|
|
echo 'wget
url' | at 01:00 |
Download url
at 1AM to current dir |
|
|
wget
--limit-rate=20k url |
Do a low
priority download (limit to 20KB/s
in this case) |
|
|
wget -nv
--spider --force-html -i bookmarks.html |
Check links in
a file |
|
|
wget --mirror
http://www.example.com/ |
Efficiently
update a local copy of a site (handy from cron) |
|
networking (Note ifconfig,
route, mii-tool, nslookup commands are obsolete) |
|
|
ethtool eth0 |
Show status of
ethernet interface eth0 |
|
|
ethtool
--change eth0 autoneg off speed 100 duplex full |
Manually set
ethernet interface speed |
|
|
iwconfig eth1 |
Show status of
wireless interface eth1 |
|
|
iwconfig eth1
rate 1Mb/s fixed |
Manually set
wireless interface speed |
|
• |
iwlist scan |
List wireless
networks in range |
|
• |
ip
link show |
List network
interfaces |
|
|
ip link set
dev eth0 name wan |
Rename
interface eth0 to wan |
|
|
ip link set
dev eth0 up |
Bring
interface eth0 up (or down) |
|
• |
ip addr show |
List addresses
for interfaces |
|
|
ip addr add
1.2.3.4/24 brd + dev eth0 |
Add (or del)
ip and mask (255.255.255.0) |
|
• |
ip route show |
List routing
table |
|
|
ip route add
default via 1.2.3.254 |
Set default
gateway to 1.2.3.254 |
|
• |
host
pixelbeat.org |
Lookup DNS ip
address for name or vice versa |
|
• |
hostname -i |
Lookup local
ip address (equivalent to host `hostname`) |
|
• |
whois
pixelbeat.org |
Lookup whois
info for hostname or ip address |
|
• |
netstat -tupl |
List internet
services on a system |
|
• |
netstat -tup |
List active
connections to/from system |
|
windows networking (Note
samba is the package that provides all this windows
specific networking support) |
|
• |
smbtree |
Find windows
machines. See also findsmb |
|
|
nmblookup -A
1.2.3.4 |
Find the
windows (netbios) name associated with ip address |
|
|
smbclient -L
windows_box |
List shares on
windows machine or samba server |
|
|
mount -t smbfs
-o fmask=666,guest //windows_box/share /mnt/share |
Mount a
windows share |
|
|
echo 'message'
| smbclient -M windows_box |
Send popup to
windows machine (off by default in XP sp2) |
|
text
manipulation (Note sed
uses stdin and stdout. Newer versions support
inplace editing with the -i option) |
|
|
sed
's/string1/string2/g' |
Replace
string1 with string2 |
|
|
sed
's/\(.*\)1/\12/g' |
Modify
anystring1 to anystring2 |
|
|
sed '/ *#/d;
/^ *$/d' |
Remove
comments and blank lines |
|
|
sed ':a;
/\\$/N; s/\\\n//; ta' |
Concatenate
lines with trailing \ |
|
|
sed 's/[
\t]*$//' |
Remove
trailing spaces from lines |
|
|
sed
's/\([`"$\]\)/\\\1/g' |
Escape shell
metacharacters active within double quotes |
|
• |
seq 10 | sed
"s/^/ /; s/ *\(.\{7,\}\)/\1/" |
Right align
numbers |
|
|
sed -n
'1000{p;q}' |
Print 1000th
line |
|
|
sed -n
'10,20p;20q' |
Print lines 10
to 20 |
|
|
sed -n 's/.*<title>\(.*\)<\/title>.*/\1/ip;T;q' |
Extract title
from HTML web page |
|
|
sed -i 42d ~/.ssh/known_hosts |
Delete a
particular line |
|
|
sort -t.
-k1,1n -k2,2n -k3,3n -k4,4n |
Sort IPV4 ip
addresses |
|
• |
echo 'Test' |
tr '[:lower:]' '[:upper:]' |
Case
conversion |
|
• |
tr -dc '[:print:]'
< /dev/urandom |
Filter non
printable characters |
|
• |
tr -s '[:blank:]'
'\t' </proc/diskstats | cut -f4 |
cut fields
separated by blanks |
|
• |
history | wc
-l |
Count lines |
|
set
operations (Note you can
export LANG=C for speed. Also these assume no
duplicate lines within a file) |
|
|
sort file1
file2 | uniq |
Union
of unsorted files |
|
|
sort file1
file2 | uniq -d |
Intersection
of unsorted files |
|
|
sort file1
file1 file2 | uniq -u |
Difference
of unsorted files |
|
|
sort file1
file2 | uniq -u |
Symmetric Difference
of unsorted files |
|
|
join
-t'\0' -a1 -a2 file1 file2 |
Union of
sorted files |
|
|
join -t'\0'
file1 file2 |
Intersection
of sorted files |
|
|
join -t'\0'
-v2 file1 file2 |
Difference of
sorted files |
|
|
join -t'\0'
-v1 -v2 file1 file2 |
Symmetric
Difference of sorted files |
|
math |
|
• |
echo '(1 +
sqrt(5))/2' | bc -l |
Quick
math (Calculate φ). See also
bc |
|
• |
echo 'pad=20;
min=64; (100*10^6)/((pad+min)*8)' | bc |
More complex (int)
e.g. This shows max FastE packet rate |
|
• |
echo 'pad=20;
min=64; print (100E6)/((pad+min)*8)' | python |
Python handles
scientific notation |
|
• |
echo 'pad=20;
plot [64:1518] (100*10**6)/((pad+x)*8)' | gnuplot
-persist |
Plot FastE
packet rate vs packet size |
|
• |
echo 'obase=16;
ibase=10; 64206' | bc |
Base
conversion (decimal to hexadecimal) |
|
• |
echo
$((0x2dec)) |
Base
conversion (hex to dec) ((shell arithmetic expansion)) |
|
• |
units -t
'100m/9.58s'
'miles/hour' |
Unit
conversion (metric to imperial) |
|
• |
units -t
'500GB' 'GiB' |
Unit
conversion (SI
to IEC
prefixes) |
|
• |
units -t '1
googol' |
Definition
lookup |
|
• |
seq 100 | (tr
'\n' +; echo 0) | bc |
Add a
column of numbers. See also
add
and
funcpy |
|
calendar |
|
• |
cal -3 |
Display a
calendar |
|
• |
cal 9 1752 |
Display a
calendar for a particular month year |
|
• |
date -d fri |
What
date is it this friday. See also
day |
|
• |
[ $(date -d "tomorrow"
+%d) = "01" ] || exit |
exit a script
unless it's the last day of the month |
|
• |
date
--date='25 Dec' +%A |
What day does
xmas fall on, this year |
|
• |
date
--date='@2147483647' |
Convert
seconds since the epoch (1970-01-01 UTC) to date |
|
• |
TZ='America/Los_Angeles'
date |
What time is
it on west coast of US (use tzselect to find TZ) |
|
• |
date --date='TZ="America/Los_Angeles"
09:00 next Fri' |
What's the
local time for 9AM next Friday on west coast US |
|
locales |
|
• |
printf "%'d\n"
1234 |
Print number
with thousands grouping appropriate to locale |
|
• |
BLOCK_SIZE=\'1
ls -l |
Use
locale thousands grouping in ls. See also
l |
|
• |
echo "I live
in `locale territory`" |
Extract info
from locale database |
|
• |
LANG=en_IE.utf8
locale int_prefix |
Lookup
locale info for specific country. See also
ccodes |
|
• |
locale | cut
-d= -f1 | xargs locale -kc | less |
List fields
available in locale database |
|
recode (Obsoletes iconv,
dos2unix, unix2dos) |
|
• |
recode -l |
less |
Show available
conversions (aliases on each line) |
|
|
recode
windows-1252.. file_to_change.txt |
Windows "ansi"
to local charset (auto does CRLF conversion) |
|
|
recode utf-8/CRLF..
file_to_change.txt |
Windows utf8
to local charset |
|
|
recode
iso-8859-15..utf8 file_to_change.txt |
Latin9
(western europe) to utf8 |
|
|
recode ../b64
< file.txt > file.b64 |
Base64 encode |
|
|
recode /qp.. <
file.qp > file.txt |
Quoted
printable decode |
|
|
recode ..HTML
< file.txt > file.html |
Text to HTML |
|
• |
recode -lf
windows-1252 | grep euro |
Lookup
table of characters |
|
• |
echo -n 0x80 |
recode latin-9/x1..dump |
Show what a
code represents in latin-9 charmap |
|
• |
echo -n 0x20AC
| recode ucs-2/x2..latin-9/x |
Show latin-9
encoding |
|
• |
echo -n 0x20AC
| recode ucs-2/x2..utf-8/x |
Show utf-8
encoding |
|
CDs |
|
|
gzip < /dev/cdrom
> cdrom.iso.gz |
Save copy of
data cdrom |
|
|
mkisofs -V
LABEL -r dir | gzip > cdrom.iso.gz |
Create cdrom
image from contents of dir |
|
|
mount -o loop
cdrom.iso /mnt/dir |
Mount the
cdrom image at /mnt/dir (read only) |
|
|
cdrecord -v
dev=/dev/cdrom blank=fast |
Clear a CDRW |
|
|
gzip -dc
cdrom.iso.gz | cdrecord -v dev=/dev/cdrom - |
Burn cdrom
image (use dev=ATAPI -scanbus to confirm dev) |
|
|
cdparanoia -B |
Rip audio
tracks from CD to wav files in current dir |
|
|
cdrecord -v
dev=/dev/cdrom -audio -pad *.wav |
Make audio CD
from all wavs in current dir (see also cdrdao) |
|
|
oggenc
--tracknum='track' track.cdda.wav -o 'track.ogg' |
Make ogg file
from wav file |
|
disk
space (See also
FSlint) |
|
• |
ls -lSr |
Show files by
size, biggest last |
|
• |
du -s * | sort
-k1,1rn | head |
Show top
disk users in current dir. See also
dutop |
|
• |
du -hs
/home/* | sort -k1,1h |
Sort paths by
easy to interpret disk usage |
|
• |
df -h |
Show free
space on mounted filesystems |
|
• |
df -i |
Show free
inodes on mounted filesystems |
|
• |
fdisk -l |
Show disks
partitions sizes and types (run as root) |
|
• |
rpm -q -a
--qf '%10{SIZE}\t%{NAME}\n' | sort -k1,1n |
List all
packages by installed size (Bytes) on rpm
distros |
|
• |
dpkg-query
-W -f='${Installed-Size;10}\t${Package}\n' | sort
-k1,1n |
List all
packages by installed size (KBytes) on deb
distros |
|
• |
dd bs=1 seek=2TB
if=/dev/null of=ext3.test |
Create a
large test file (taking no space). See also
truncate |
|
• |
> file |
truncate data
of file or create an empty file |
|
monitoring/debugging |
|
• |
tail -f /var/log/messages |
Monitor messages
in a log file |
|
• |
strace -c ls
>/dev/null |
Summarise/profile
system calls made by command |
|
• |
strace -f -e
open ls >/dev/null |
List system
calls made by command |
|
• |
ltrace -f -e
getenv ls >/dev/null |
List library
calls made by command |
|
• |
lsof
-p
$$ |
List paths
that process id has open |
|
• |
lsof ~ |
List processes
that have specified path open |
|
• |
tcpdump not
port 22 |
Show
network traffic except ssh. See also
tcpdump_not_me |
|
• |
ps -e -o pid,args
--forest |
List processes
in a hierarchy |
|
• |
ps -e -o pcpu,cpu,nice,state,cputime,args
--sort pcpu | sed '/^ 0.0 /d' |
List processes
by % cpu usage |
|
• |
ps -e
-orss=,args= | sort -b -k1,1n | pr -TW$COLUMNS |
List
processes by mem (KB) usage. See also
ps_mem.py |
|
• |
ps -C
firefox-bin -L -o pid,tid,pcpu,state |
List all
threads for a particular process |
|
• |
ps -p 1,2 |
List info for
particular process IDs |
|
• |
last reboot |
Show system
reboot history |
|
• |
free -m |
Show amount of
(remaining) RAM (-m displays in MB) |
|
• |
watch -n.1 'cat
/proc/interrupts' |
Watch
changeable data continuously |
|
• |
udevadm
monitor |
Monitor udev
events to help configure rules |
|
system information (see
also
sysinfo) ('#' means root access is required) |
|
• |
uname -a |
Show kernel
version and system architecture |
|
• |
head -n1 /etc/issue |
Show name and
version of distribution |
|
• |
cat /proc/partitions |
Show all
partitions registered on the system |
|
• |
grep MemTotal
/proc/meminfo |
Show RAM total
seen by the system |
|
• |
grep "model
name" /proc/cpuinfo |
Show CPU(s)
info |
|
• |
lspci -tv |
Show PCI info |
|
• |
lsusb -tv |
Show USB info |
|
• |
mount | column
-t |
List mounted
filesystems on the system (and align output) |
|
• |
grep -F
capacity: /proc/acpi/battery/BAT0/info |
Show state of
cells in laptop battery |
|
# |
dmidecode -q |
less |
Display SMBIOS/DMI
information |
|
# |
smartctl -A /dev/sda
| grep Power_On_Hours |
How long has
this disk (system) been powered on in total |
|
# |
hdparm -i /dev/sda |
Show info
about disk sda |
|
# |
hdparm -tT /dev/sda |
Do a read
speed test on disk sda |
|
# |
badblocks -s /dev/sda |
Test for
unreadable blocks on disk sda |
|
interactive (see also
linux keyboard shortcuts) |
|
• |
readline |
Line editor
used by bash, python, bc, gnuplot, ... |
|
• |
screen |
Virtual
terminals with detach capability, ... |
|
• |
mc |
Powerful file
manager that can browse rpm, tar, ftp, ssh, ... |
|
• |
gnuplot |
Interactive/scriptable
graphing |
|
• |
links |
Web browser |
|
• |
xdg-open
. |
open a file or
url with the registered desktop application |
