sed -n '/^function h\(\)/,/^}/p' script.sh

Extract a bash function

I often need to extract a function from a bash script and this command will do it.
Sample Output
$ sed -n '/^function h\(\)/,/^}/p' .bash_profile
function h() {
    if [ -z "$1" ]
    then
        history
    else
        history | grep "$@"
    fi
}

8
By: haivu
2009-10-19 07:55:35

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    0
    col() { awk '{print $('$(echo $* | sed -e s/-/NF-/g -e 's/ /),$(/g')')}'; }
    tekniq · 2014-06-05 18:01:31 0
  • Had trouble with the other function, because of missing semicolons. (According to my bash on OS X)


    0
    function cdf () { [ -f $1 ] && { cd $(dirname $1); } || { cd $1 ; }; pwd; };
    Josso · 2012-09-08 10:50:58 1
  • This Anti-TarBomb function makes it easy to unpack a .tar.gz without worrying about the possibility that it will "explode" in your current directory. I've usually always created a temporary folder in which I extracted the tarball first, but I got tired of having to reorganize the files afterwards. Just add this function to your .zshrc / .bashrc and use it like this; atb arch1.tar.gz and it will create a folder for the extracted files, if they aren't already in a single folder. This only works for .tar.gz, but it's very easy to edit the function to suit your needs, if you want to extract .tgz, .tar.bz2 or just .tar. More info about tarbombs at http://www.linfo.org/tarbomb.html Tested in zsh and bash. UPDATE: This function works for .tar.gz, .tar.bz2, .tgz, .tbz and .tar in zsh (not working in bash): atb() { l=$(tar tf $1); if [ $(echo "$l" | wc -l) -eq $(echo "$l" | grep $(echo "$l" | head -n1) | wc -l) ]; then tar xf $1; else mkdir ${1%.t(ar.gz||ar.bz2||gz||bz||ar)} && tar xf $1 -C ${1%.t(ar.gz||ar.bz2||gz||bz||ar)}; fi ;} UPDATE2: From the comments; bepaald came with a variant that works for .tar.gz, .tar.bz2, .tgz, .tbz and .tar in bash: atb() {shopt -s extglob ; l=$(tar tf $1); if [ $(echo "$l" | wc -l) -eq $(echo "$l" | grep $(echo "$l" | head -n1) | wc -l) ]; then tar xf $1; else mkdir ${1%.t@(ar.gz|ar.bz2|gz|bz|ar)} && tar xf $1 -C ${1%.t@(ar.gz|ar.bz2|gz|bz|ar)}; fi ; shopt -u extglob} Show Sample Output


    10
    atb() { l=$(tar tf $1); if [ $(echo "$l" | wc -l) -eq $(echo "$l" | grep $(echo "$l" | head -n1) | wc -l) ]; then tar xf $1; else mkdir ${1%.tar.gz} && tar xf $1 -C ${1%.tar.gz}; fi ;}
    elfreak · 2010-10-16 05:50:32 5
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    1
    function fcd () { [ -f $1 ] && { cd $(dirname $1); } || { cd $1 ; } pwd }
    relay · 2009-09-03 18:58:13 0
  • In order to write bash-scripts, I often do the task manually to see how it works. I type ### at the start of my session. The function fetches the commands from the last occurrence of '###', excluding the function call. You could prefix this with a here-document to have a proper script-header. Delete some lines, add a few variables and a loop, and you're ready to go. This function could probably be much shorter...


    1
    quickscript () { filename="$1"; history | cut -c 8- | sed -e '/^###/{h;d};H;$!d;x' | sed '$d' > ${filename:?No filename given} }
    joedhon · 2014-02-09 12:19:29 0
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    2
    function ytmp3() { while (($#)); do (cd ~/Music; echo "Extracting mp3 from $(youtube-dl -e $1)"; /usr/bin/youtube-dl -q -t --extract-audio --audio-format mp3 $1); shift; done ; }
    snipertyler · 2013-08-08 06:44:29 0

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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