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Cas
Asked: 2021-01-22 05:44:31 +0800 CST

Using xargs and variables

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Hey I have a question.

This is the command that I'm using (at the place of echo $file is a different command. I simplified it):

find /home/cas/plex-media/series/ -type f -name "*" ! -name "*.srt" -print0 | sort | xargs -0 -n1 -I{} file={} && echo $file

It says that file={} isn't a command, which is true because it is a variable. I need to set that variable to one line of the output each time, just as xargs does with a command. But I need it to fill the variable and then run that command with that variable for each line of the ouput of sort.

Example:

As input (aka ouput of sort):

/home/cas/plex-media/series/Pokémon/Season 1/Pokémon - S01E01 - Pokémon - I Choose You!.mp4
/home/cas/plex-media/series/Pokémon/Season 1/Pokémon - S01E02 - Pokémon Emergency.mp4
/home/cas/plex-media/series/Pokémon/Season 1/Pokémon - S01E03 - Ash Catches a Pokémon.mp4

How I want it to be executed every time by xargs:

file=/home/cas/plex-media/series/Pokémon/Season 1/Pokémon - S01E01 - Pokémon - I Choose You!.mp4 && echo /home/cas/plex-media/series/Pokémon/Season 1/Pokémon - S01E01 - Pokémon - I Choose You!.mp4
file=/home/cas/plex-media/series/Pokémon/Season 1/Pokémon - S01E02 - Pokémon Emergency.mp4 && echo /home/cas/plex-media/series/Pokémon/Season 1/Pokémon - S01E02 - Pokémon Emergency.mp4
file=/home/cas/plex-media/series/Pokémon/Season 1/Pokémon - S01E03 - Ash Catches a Pokémon.mp4 && echo /home/cas/plex-media/series/Pokémon/Season 1/Pokémon - S01E03 - Ash Catches a Pokémon.mp4

I can't just do echo {} as I have multiple places is my command where {} needs to be filled in and I have quite alot of command {} $(other command {}). So I replaced all those places where the output of sort needs to go with the variable $file. Because then xargs only needs to change the variable once and run the command. Then change the variable and run the command again etc etc.

I hope that you understand my problem and what my goal is. Can you help me?

Thanks!

command-line

1 Answers

  1. Best Answer

    Use xargs with sh -c (orbash -c if needed):

    find ...  -print0 |  sort -z | xargs -0 -n1 -I{} sh -c 'file=$1; echo "$file";' xargs-sh {}

    If you don't need the sort step, better avoid xargs and use find -exec :

    find /home/cas/plex-media/series/ -type f ! -name "*.srt" \
  -exec sh -c 'file=$1; echo "$file";' find-sh {} \;

    For why we need this strange notation sh -c '...' sh {} , please see Is it possible to use find -exec sh -c safely?

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