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Functions

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Terminal - All commands - 12,342 results
declare -f [ function_name ]
set | fgrep " ()"
2009-10-22 17:48:54
User: haivu
Functions: fgrep set
1

If you issue the "set" command, you'll see a list of variables and functions. This command displays just those functions' names.

awk 'BEGIN{dir=DIR?DIR:ENVIRON["PWD"];l=split(dir,parts,"/");last="";for(i=1;i<l+1;i++){d=last"/"parts[i];gsub("//","/",d);system("ls -ld \""d"\"");last=d}}'
2009-10-22 16:28:07
User: arcege
Functions: awk
-1

Handled all within awk. Takes the value from $PWD and constructs directory structures and runs commands against them. The gsub() call is not necessary, but added for better visibility.

If a variable DIR is given on the awk command-line, then that directory is used instead:

awk -vDIR=$HOME/.ssh 'BEGIN{dir=DIR?...}'
shuf -i 1-49 | head -n6 | sort -n| xargs
2009-10-22 12:54:08
User: ioggstream
Functions: head sort
5

note the xargs at the end

pushd .> /dev/null; cd /; for d in `echo $OLDPWD | sed -e 's/\// /g'`; do cd $d; echo -n "$d "; ls -ld .; done; popd >/dev/null
2009-10-22 12:32:11
User: syladmin
Functions: cd echo ls sed
Tags: permissions
0

Can easily be scripted in order to show permission "tree" from any folder. Can also be formated with

column -t

{ pushd .> /dev/null; cd /; for d in `echo $OLDPWD | sed -e 's/\// /g'`; do cd $d; echo -n "$d "; ls -ld .; done; popd >/dev/null ; } | column -t

from http://www.commandlinefu.com/commands/view/3731/using-column-to-format-a-directory-listing

echo $(shuf -i 1-49 | head -n6 | sort -n)
flip -u <filenames>
touch -r "$FILE1" "$FILE2"
2009-10-21 13:53:59
User: kobayashison
Functions: touch
2

atime and mtime timestamps of $FILE2 is changed according to the ones of $FILE1. If $FILE2 doesn't exist is created.

shopt -s dotglob
PROMPT_COMMAND="history -a"
2009-10-21 12:33:25
User: danam
Tags: history bash,
2

This could be added to .bashrc. Background: Linux usually saves history only on clean exit of shell. If shell ends unclean, history is lost. Also numerous terminals might confuse their history. With this variable set, history is immedeately written, accessible to all other open shells.

wmsetbg -s -u path_to_wallpaper
2009-10-21 11:23:54
User: eastwind
1

set directly the wallpaper on windowmaker , use this command with display of imagemagick :)

mencoder mf://image1.jpg,image2.jpg,image3.jpg -mf w=800:h=600:fps=25:type=jpeg -ovc copy -oac copy -o output.avi
2009-10-21 09:17:22
User: eastwind
-1

syntax :

mencoder mf://filemask -mf

option availble for mf :

* w=value : the width of the output, by d?fault : autodetected

* h=value : height of the output, by default : autodetected

* fps=value : framerate of the output, by default : 25

* type=value : file format type input , avaible: jpeg, png, tga, sgi

mencoder mf://*.jpg -mf w=800:h=600:fps=25:type=jpeg -ovc lavc -lavcopts vcodec=mpeg4 -oac copy -o output.avi
2009-10-21 09:14:04
User: eastwind
0

syntax :

mencoder mf://filemask -mf

option availble for mf :

* w=value : the width of the output, by d?fault : autodetected

* h=value : height of the output, by default : autodetected

* fps=value : framerate of the output, by default : 25

* type=value : file format type input , avaible: jpeg, png, tga, sgi

ffmpeg -i input.mov -b 4096k -vcodec msmpeg4v2 -acodec pcm_u8 output.avi
2009-10-21 05:44:31
User: oracular
1

Convert those .mov files that your digital camera makes to .avi

Adjust the bitrate (-b) to get the appropriate file size. A larger bitrate produces a larger (higher quality) .avi file and smaller bitrate produces a smaller (lower quality) .avi file.

Requires ffmpeg (see man page for details)

(tested with canon camera MOV files)

Other examples:

ffmpeg -i input.mov -sameq -vcodec msmpeg4v2 -acodec pcm_u8 output.avi ffmpeg -i input.mov -b 1024k -vcodec msmpeg4v2 -acodec pcm_u8 output.avi
awk 'FNR==5' <file>
2009-10-20 22:52:41
User: dennisw
Functions: awk
1

Just one character longer than the sed version ('FNR==5' versus -n 5p). On my system, without using "exit" or "q", the awk version is over four times faster on a ~900K file using the following timing comparison:

testfile="testfile"; for cmd in "awk 'FNR==20'" "sed -n '20p'"; do echo; echo $cmd; eval "$cmd $testfile"; for i in {1..3}; do time for j in {1..100}; do eval "$cmd $testfile" >/dev/null; done; done; done

Adding "exit" or "q" made the difference between awk and sed negligible and produced a four-fold improvement over the awk timing without the "exit".

For long files, an exit can speed things up:

awk 'FNR==5{print;exit}' <file>
seg() { for b in $(echo $1); do for x in $(seq 10); do echo $b.$x; done; done }
seg() { echo -e "$1" | while read LINE; do for b in $(seq 10); do echo $LINE.$b; done; done; }
echo -e "n\np\n1\n\n\nt\n8e\nw" | fdisk /dev/sdX
2009-10-20 16:21:54
User: sud0er
Functions: echo fdisk
Tags: Linux fdisk
-1

This is a bit hacky, but if you're setting up a bunch of new LUNs, it can save a bunch of time. Also check out sfdisk. The fdisk will fail if, for example, a partition table already exists.

teste.txt < cut -d : -f 1,5 /etc/passwd | tr : \\t | tr a-z A-Z | cat teste.txt
defaults write com.macromates.textmate OakDefaultLanguage 17994EC8-6B1D-11D9-AC3A-000D93589AF6
2009-10-20 07:10:34
User: vigo
Functions: write
-1

When you press "cmd+n" in TextMate, you can have "HTML" language as default document format... You can also define other languages too. You need to know the UUID of your language bundle.

ssh [email protected] 'dd if=sda.img' | dd of=/dev/sda
dd if=/dev/sda | ssh [email protected] 'dd of=sda.img'
for a in bzip2 lzma gzip;do echo -n>$a;for b in $(seq 0 256);do dd if=/dev/zero of=$b.zero bs=$b count=1;c=$(date +%s%N);$a $b.zero;d=$(date +%s%N);total=$(echo $d-$c|bc);echo $total>>$a;rm $b.zero *.bz2 *.lzma *.gz;done;done
2009-10-20 01:00:51
User: matthewbauer
Functions: bzip2 date dd echo seq
3

See: http://imgur.com/JgjK2.png for example.

Do some serious benchmarking from the commandline. This will write to a file with the time it took to compress n bytes to the file (increasing by 1).

Run:

gnuplot -persist <(echo "plot 'lzma' with lines, 'gzip' with lines, 'bzip2' with lines")

To see it in graph form.

cat private-file | gpg2 --encrypt --armor --recipient "Disposable Key" | mailx -s "Email Subject" [email protected]
2009-10-19 20:38:37
User: slashdot
Functions: cat mailx
2

This is a quick and easy way of encrypting files in a datastream, without ever really creating an output file from gpg. Useful with cron also, when file(s) have to be sent based on a set schedule.

sed -ne '/^Package: \(.*\)/{s//\1/;h;};/^Installed-Size: \(.*\)/{s//\1/;G;s/\n/ /;p;}' /var/lib/dpkg/status | sort -rn
2009-10-19 19:01:17
User: arcege
Functions: sed sort
-3

Use the hold space to preserve lines until data is needed.