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foreach - Bash alias to execute command on each line (toast.ooo)

submitted 2 days ago by cm0002@toast.ooo to c/linux@programming.dev

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Just wanted to share an alias I have in use and found it useful again. It's a simple wrapper around xargs, which I always forget how to use properly, so I set up an alias for. All it does is operate on each line on stdout.

The arguments are interpreted as the command to execute. The only thing to remember is using the {} as a placeholder for the input line. Look in the examples to understand how its used.
# Pipe each line and execute a command. The "{}" will be replaced by the line.
#
# Example:
#   cat url.txt | foreach echo download {} to directory
#   ls -1 | foreach echo {}
#   find . -maxdepth 2 -type f -name 'M*' | foreach grep "USB" {}
alias foreach='xargs -d "\n" -I{}'
Useful for quickly operating on each line of a file (in example to download from list of urls) or do something with any stdout output line by line. Without remembering or typing a for loop in terminal.

OC by @thingsiplay@lemmy.ml

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[–] stewie410@programming.dev 2 points 2 days ago* (last edited 2 days ago)

Or use a while-read loop anyway?

while read -r foo; do
  cmd "${foo}" 
done < <(ls -1)

(But don't script ls)

The find example should just use -exec grep "USB" {} + also, though -exec generally is the correct way to do this.