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runs a bash script in debugging mode

Show Sample Output

bash -x ./post_to_commandlinefu.sh

nottings · 2009-02-25 19:10:21 27

Instead of writing a multiline if/then/else/fi construct you can do that by one line

instead of writing: if [[ "$1" == "$2" ]]; then echo "$1 is equal $2" else echo "$1 differs from $2" fi do write: [[ "$1" == "$2" ]] && echo "$1 is equal $2" || echo "$1 differs from $2"
This is sample output - yours may be different.
26

[[ test_condition ]] && if_true_do_this || otherwise_do_that

stallmer · 2009-02-20 21:45:21 33
Display a list of committers sorted by the frequency of commits

Use this command to find out a list of committers sorted by the frequency of commits. Show Sample Output
This is sample output - yours may be different.
```
5 john
5 sal
3 kate
2 joe
1 fred
1 mark
```
26

svn log -q|grep "|"|awk "{print \$3}"|sort|uniq -c|sort -nr

psytek · 2009-02-17 21:37:03 15
List the number and type of active network connections
This is sample output - yours may be different.
26

netstat -ant | awk '{print $NF}' | grep -v '[a-z]' | sort | uniq -c

himynameisthor · 2009-02-05 18:02:59 36
check the status of 'dd' in progress (OS X)

Sends SIGINFO to the process. This is a BSD feature OS X inherited. You must have the terminal window executing dd selected when entering CTRL + T for this to work. Show Sample Output
This is sample output - yours may be different.
```
load: 1.24  cmd: dd 4960 uninterruptible 0.26u 4.59s
476897+0 records in
476896+0 records out
244170752 bytes transferred in 323.318769 secs (755201 bytes/sec)
```
25

CTRL + T

unixmonkey44467 · 2012-12-19 02:21:41 21
A child process which survives the parent's death (for sure)

Test scenario: * Open xterm (or konsole, ...) * Start xeyes with: ( xeyes & ) * Close the xterminal The xeyes process should be still running.
This is sample output - yours may be different.
25

( command & )

wiburg · 2011-01-07 19:06:30 21
prevent accidents while using wildcards

alternative for "echo rm *.txt". Just doubletab the command you are willing to use and it will show you the affected files. Show Sample Output
This is sample output - yours may be different.
```
linux:/tmp # rm *.txt
wildcard.txt   tab.txt
```
25

rm *.txt <TAB> <TAB>

boschi · 2010-11-04 13:58:15 11
Opens vi/vim at pattern in file

Open up vi or vim at the first instance of a pattern in [file]. Useful if you know where you want to be, like "PermitRootLogin" in sshd_config. Also, vi +10 [file] will open up a file at line 10. VERY useful when you get "error at line 10" type of output.
This is sample output - yours may be different.
25

vi +/pattern [file]

punkwalrus · 2010-04-24 22:15:12 7
April Fools' Day Prank

Add this to a fiend's .bashrc. PROMPT_COMMAND will run just before a prompt is drawn. RANDOM will be between 0 and 32768; in this case, it'll run about 1/10th of the time. \033 is the escape character. I'll call it \e for short. \e7 -- save cursor position. \e[%d;%dH -- move cursor to absolute position \e[4%dm \e[m -- draw a random color at that point \e8 -- restore position.
This is sample output - yours may be different.
25

PROMPT_COMMAND='if [ $RANDOM -le 3200 ]; then printf "\0337\033[%d;%dH\033[4%dm \033[m\0338" $((RANDOM%LINES+1)) $((RANDOM%COLUMNS+1)) $((RANDOM%8)); fi'

hotdog003 · 2010-04-01 06:52:32 16
Press Any Key to Continue

Halt script progress until a key has been pressed. Source: http://bash-hackers.org/wiki/doku.php/mirroring/bashfaq/065
This is sample output - yours may be different.
25

read -sn 1 -p "Press any key to continue..."

kalaxy · 2009-11-05 21:53:23 11
Get your external IP address

Yeah I know it's been up here a million times, but this service is a really clean and nice one. Nothing but your IP address on it. Actually I was to write something like this, and noticed this on appspot... ;) Show Sample Output
This is sample output - yours may be different.
```
88.224.62.157
```
25

curl ip.appspot.com

ktoso · 2009-10-31 21:11:10 12
List installed deb packages by size
This is sample output - yours may be different.
25

dpkg-query -Wf '${Installed-Size}\t${Package}\n' | sort -n

raspi · 2009-10-25 03:23:51 15
backup all your commandlinefu.com favourites to a plaintext file

Usage: clfavs username password num_favourite_commands file_in_which_to_backup
This is sample output - yours may be different.
25

clfavs(){ URL="http://www.commandlinefu.com";wget -O - --save-cookies c --post-data "username=$1&password=$2&submit=Let+me+in" $URL/users/signin;for i in `seq 0 25 $3`;do wget -O - --load-cookies c $URL/commands/favourites/plaintext/$i >>$4;done;rm -f c;}

suhasgupta · 2009-09-30 16:43:08 24
send echo to socket network

this command will send a message to the socket 25 on host 192.168.1.2 in tcp. works on udp and icmp understand only IP address, not hostname. on the other side (192.168.1.2), you can listen to this socket and test if you receive the message. easy to diagnose a firewall problem or not.
This is sample output - yours may be different.
25

echo "foo" > /dev/tcp/192.168.1.2/25

mobidyc · 2009-09-12 16:48:05 16
Schedule a script or command in x num hours, silently run in the background even if logged out

doesn't require "at", change the "2h" to whatever you want... (deafult unit for sleep is seconds)
This is sample output - yours may be different.
25

( ( sleep 2h; your-command your-args ) & )

sitaram · 2009-08-19 17:39:11 12
Go to parent directory of filename edited in last command

Uses the last argument of the last executed command, and gets the directory name from it. Use $!:t for the filename alone, without the dirname. Show Sample Output
This is sample output - yours may be different.
```
user@host:/home$ vim /path/to/file.txt
user@host:/home$ cd !$:h
user@host:/path/to$ 
```
25

cd !$:h

lingo · 2009-08-07 00:37:08 10
Draw a Sierpinski triangle

OK, not the most useful but a good way to impress friends. Requires the "display" command from ImageMagick.
This is sample output - yours may be different.
25

perl -e 'print "P1\n256 256\n", map {$_&($_>>8)?1:0} (0..0xffff)' | display

dstahlke · 2009-07-08 17:50:23 28
Run a long job and notify me when it's finished

You will need libnotify-bin for this to work: sudo aptitude install libnotify-bin
This is sample output - yours may be different.
25

./my-really-long-job.sh && notify-send "Job finished"

root · 2009-05-07 15:50:27 16
Make anything more awesome

Pipe any command through figlet to make the output more awesome. Example: ls | figlet Show Sample Output
This is sample output - yours may be different.
```
_          _ _                            _     _ 
| |__   ___| | | ___   __      _____  _ __| | __| |
| '_ \ / _ \ | |/ _ \  \ \ /\ / / _ \| '__| |/ _` |
| | | |  __/ | | (_) |  \ V  V / (_) | |  | | (_| |
|_| |_|\___|_|_|\___/    \_/\_/ \___/|_|  |_|\__,_|
```
25

command | figlet

isaacs · 2009-05-03 21:20:46 16

List all files opened by a particular command

List all file opened by a particular command based on it's command name. Show Sample Output

lsof -c dhcpd

d4n3sh · 2009-04-17 07:18:38 11

Nicely display permissions in octal format with filename

Nicely display permissions in octal format and filename for a given directory Show Sample Output
This is sample output - yours may be different.
```
-rwxrwxr-x 775 argv.csh
-rwxr-xr-x 755 array.sh
-rwxrwxr-x 775 backup
-rw-r--r-- 644 bash_trap
-rw-r--r-- 644 bash_wait
```
25

stat -c '%A %a %n' *

servermanaged · 2009-04-09 10:44:56 14
recursive search and replace old with new string, inside files

recursively traverse the directory structure from . down, look for string "oldstring" in all files, and replace it with "newstring", wherever found also: grep -rl oldstring . |xargs perl -pi~ -e 's/oldstring/newstring'
This is sample output - yours may be different.
25

$ grep -rl oldstring . |xargs sed -i -e 's/oldstring/newstring/'

netfortius · 2009-03-03 20:10:19 26
shut of the screen.
This is sample output - yours may be different.
25

xset dpms force standby

zooooz · 2009-03-03 16:54:56 17
Create a single-use TCP (or UDP) proxy

Redirect the local port 2000 to the remote port 3000. The same but UDP: nc -u -l -p 2000 -c "nc -u example.org 3000" It may be used to "convert" TCP client to UDP server (or viceversa): nc -l -p 2000 -c "nc -u example.org 3000"
This is sample output - yours may be different.
25

nc -l -p 2000 -c "nc example.org 3000"

prayer · 2009-03-01 21:28:39 21
read manpage of a unix command as pdf in preview (Os X)
This is sample output - yours may be different.
25

man -t UNIX_COMMAND | open -f -a preview

vranx · 2009-02-24 13:12:16 26
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posts an xml file to a webservice with curl

Show drive names next to their full serial number (and disk info)

Add prefix onto filenames

Best to try first with -n flag, to preview

Convert seconds to [DD:][HH:]MM:SS

Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Check if the Debian package was used since its installation/upgrade.

This script compares the modification date of /var/lib/dpkg/info/${package}.list and all the files mentioned there. It could be wrong on noatime partitions. Here is non-oneliner: #!/bin/sh package=$1; list=/var/lib/dpkg/info/${package}.list; inst=$(stat "$list" -c %X); cat $list | ( while read file; do if [ -f "$file" ]; then acc=$(stat "$file" -c %X); if [ $inst -lt $acc ]; then echo used $file exit 0 fi; fi; done exit 1 )

Remove a range of lines from a file

Execute a file in vim with the #!/bin/interpreter in the first line

exit without saving history

this exits bash without saving the history. unlike explicitly disabling the history in some way, this works anywhere, and it works if you decide *after* issuing the command you don't want logged, that you don't want it logged ... $$ ( or ${$} ) is the pid of the current bash instance this also works perfectly in shells that don't have $$ if you do something like $ kill -9 `readlink /proc/self`

Rename all files which contain the sub-string 'foo', replacing it with 'bar'

Would this command line achieve the desired function? My CLI knowledge is not great so this could certainly be wrong. It is merely a suggestion for more experienced uses to critique. Best wishes roly :-)

Convert CSV to JSON

Replace 'csv_file.csv' with your filename.

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