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Terminal - All commands - 11,951 results
function crtonl { perl -i -ape 's/\r/\n/g;' $* ; }
2009-03-25 20:28:32
User: totoro
Functions: perl
Tags: files
-2

Many Mac OS X programs, especially those in Microsoft:Office, create ASCII files with lines terminated by CRs (carriage returns). Most Unix programs expect lines separated by NLs (newlines). This little command makes it trivial to convert them.

function headers { head -1 $* | tr ',' '\12' | pr -t -n ; }
2009-03-25 20:07:47
User: totoro
Functions: head pr tr
Tags: CSV headers
0

This little command (function) shows the CSV header fields (which are field names separated by commas) as an ordered list, clearly showing the fields and their order.

function t { ls -ltch $* | head -20 ; }
2009-03-25 20:05:52
User: totoro
Functions: head ls
0

Coming back to a project directory after sometime elsewhere?

Need to know what the most recently modified files are?

This little function "t" is one of my most frequent commands.

I have a tcsh alias for it also:

alias t 'ls -ltch \!* | head -20'

find . -type f -depth -3 -mtime -5
2009-03-25 19:54:06
User: totoro
Functions: find
-2

Ever wanted to find the most recently modified files, but couldn't remember exactly where they were in a project directory with many subdirectories? The "find" command, using a combination of "-mtime -N" and "-depth -D" can be used to find those files. If your directory structure isn't very deep, just omit the "-depth -D", but if your directory structure is very deep, then you can limit the depth of the traversal using "-depth -D", where "D" is the maximum number of directory levels to descend.

perl -e 'print scalar localtime $ARGV[0],"\n" ' epoch
du -hS / | perl -ne '(m/\d{3,}M\s+\S/ || m/G\s+\S/) && print'
2009-03-25 18:06:53
User: Alioth
Functions: du perl
6

Finds all directories containing more than 99MB of files, and prints them in human readable format. The directories sizes do not include their subdirectories, so it is very useful for finding any single directory with a lot of large files.

curl -i -X HEAD http://localhost/
rpm -q --qf "%{VERSION}\n" redhat-release
2009-03-25 16:46:14
User: atoponce
Functions: rpm
2

In this case, I'm getting the package version for 'redhat-release', but of course, this can be applied to any package installed on the filesystem. This is very handy in scripts that need to determine just the version of the package, without the package name and all the sed and grep hackery to get to the data you want. To find out all the support format strings that 'rpm --qf' supports:

rpm --querytags
find /proc -regex '/proc/[0-9]+/smaps' -exec grep -l "$PATH_REGEX" {} \; | cut -d'/' -f2
2009-03-25 16:33:44
User: juddmaltin
Functions: cut find grep
1

faster than lsof by at least x2 on my box.

rm -rf `find . -type d -name .svn`
wc -l `find . -name *.php`
find . -wholename './.snapshot' -prune -o -print
2009-03-25 13:52:01
User: jeffaz
Functions: find
3

This can be useful for those who have mounted NetApp file-systems with snapshot activated.

netstat -antuwp | egrep "(^[^t])|(^tcp.*LISTEN)"
test.bat parm1 parm2 parm3
2009-03-25 12:27:18
User: lansa
Functions: test
-34

I am using .bat commands to execute Curl commands for Twitter API

wget -q http://xyz.gpg -O- | sudo apt-key add -
2009-03-25 12:18:36
User: gnuyoga
Functions: sudo wget
Tags: wget apt-key
4

when we add a new package to a aptitude (the debian package manager) we need to add the gpg, otherwise it will show warning / error for missing key

wget -q http://xyz.gpg -O- | sudo apt-key add -
2009-03-25 12:18:29
User: gnuyoga
Functions: sudo wget
Tags: apt-key
2

when we add a new package to a aptitude (the debian package manager) we need to add the gpg, otherwise it will show warning / error for missing key

echo "obase=2; 27" | bc -l
2009-03-25 09:54:50
User: polar
Functions: bc echo
Tags: bc
20

Easily convert numbers to their representations in different bases. Passing

"ibase=16; obase=8; F2A"

to bc will convert F2A (3882 in decimal) from Hex to Octal, and so on.

arp -s $(route -n | awk '/^0.0.0.0/ {print $2}') \ $(arp -n | grep `route -n | awk '/^0.0.0.0/ {print $2}'`| awk '{print $3}')
echo "$math_expr" | bc -l
2009-03-25 09:46:01
User: polar
Functions: bc echo
Tags: bc
2

Useful for quick calculations at the command line. $math_expr is any arithmetic expression (see sample output):

4.5*16+3^2

s(3.1415926/2)

More options in the bc man page.

ls /some/directory | sed -rn -e 's/input_file_regex/mv -v & output_file_name/p' | sh
2009-03-25 09:20:15
User: polar
Functions: ls sed
Tags: bash sed
-2

Allows for quick mass renaming, assuming the user has some familiarity with regular expressions. Basically, it replaces the original_file_name in the output of ls with

"mv -v original_file_name new_file_name"

and passes the output to sh.

alias showip="ifconfig eth0 | grep 'inet addr:' | sed 's/.*addr\:\(.*\) Bcast\:.*/\1/'"
2009-03-25 07:50:12
User: dizzgo
Functions: alias
Tags: ifconfig alias IP
0

parses the output of ifconfig to show only the configured ip address (in this case from interface eth0).

the regexp is quick'n'dirty im sure it can be done in a better way.

--> this alias does not show your "internet ip" when you're in a nat-environment

cdrecord -v dev=/dev/cdrom yourimage.iso
2009-03-25 07:31:54
User: dizzgo
Functions: cdrecord
3

cdrecord must be installed.

usefull alias:

alias burniso='cdrecord -v dev=/dev/cdrom'

now iso burning is like.

burniso image.iso
do-release-upgrade
2009-03-25 07:25:33
User: dizzgo
Tags: Ubuntu
-1

release upgrades are major upgrades as from 8.04 to 8.10 or from 8.10 to 9.04

update-manager-core must be installed:

sudo apt-get install update-manager-core

in some cases you must edit '/etc/update-manager/release-upgrades' and set 'Prompt=normal'

gs -sDEVICE=pswrite -sOutputFile=- -q -dNOPAUSE With-Fonts.pdf -c quit | ps2pdf - > No-Fonts.pdf
2009-03-25 03:46:00
User: qubyte
Functions: gs
1

It's sometimes useful to strip the embedded fonts from a pdf, for importing into something like Inkscape. Be warned, this will increase the size of a pdf substantially.

I tried this with only gs writing with -sDEVICE=pdfwrite but it doesn't seem to work, so I just pipe postscript output to ps2pdf for the same effect.

swapoff -a ; swapon -a
2009-03-25 03:30:41
User: alperyilmaz
Functions: swapoff swapon
Tags: swapoff swapon
10

When you run a memory intensive application (VirtualBox, large java application, etc) swap area is used as soon as memory becomes insufficient. After you close the program, the data in swap is not put back on memory and that decreases the responsiveness. Swapoff disables the swap area and forces system to put swap data be placed in memory. Since running without a swap area might be detrimental, swapon should be used to activate swap again.

Both swapoff and swapon require root privileges.