Bash Shell Scripting One Liners

Finding Code in PHP files

This will list all .php files that contain a certain string. Just replace {token} with whatever string you’re searching for. I use this when I have to automate figuring out which PHP files include other PHP files.

find ./ -name '*.php' | sed 's/^\(.*\)$/"\1"/g' | xargs grep -lF '{token}'

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Handling file names with Spaces with find and xargs find can find files with spaces in their file names. This makes xargs go crazy unless you:

find ./ -type f -print0 | xargs -0 ...

The -print0 instructs find to end each search results with a NUL character. The -0 instructs xargs to use a NUL character as a separator. Neato

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Example of how to find missing sequential files. I have a bunch of files named: 001.zip, 002.zip, 003.zip, etc. This helps me find if there are any missing files.

c=318; until [ $c -lt 1 ]; do a=`printf '%03d' $c`; \\
if [ ! -f "${a}.zip" ]; then echo "Missing ${a}.zip"; fi; let c-=1;

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Determining what directory a shell script is in

First the code:

_DIR=`dirname "$(readlink -f $0)"`

This is useful if the shell script calls other scripts and is run within cron. Use the above command to change to a known directory and then run other scripts / commands.