Set executable permissions only to executable files

while IFS= read -r -u3 -d $'\0' file; do file "$file" | egrep -q 'executable|ELF' && chmod +x "$file"; done 3< <(find . -type f -print0)
If you make a mess (like I did) and you removed all the executable permissions of a directory (or you set executable permissions to everything) this can help. It supports spaces and other special characters in the file paths, but it will work only in bash, GNU find and GNU egrep. You can complement it with these two commands: 1. add executable permission to directories: find . type d -print0 | xargs -0 chmod +x 2. and remove to files: find . type d -print0 | xargs -0 chmod -x Or, in the same loop: while IFS= read -r -u3 -d $'\0' file; do case $(file "$file" | cut -f 2- -d :) in :*executable*|*ELF*|*directory*) chmod +x "$file" ;; *) chmod -x "$file" ;; esac || break done 3< <(find . -print0) Ideas stolen from Greg's wiki:

By: keymon
2011-08-18 15:37:23

What Others Think

aka chmod -R +X
bashrc · 573 weeks and 2 days ago
Not, chmod -R +X only works for directories or files that already have a execution bit set: cp /bin/bash . chmod -x bash chmod +X bash ls -l total 796 -rw-r--r-- 1 hrivas hrivas 811156 Aug 18 13:46 bash From chmod(1) manual: "execute/search only if the file is a directory or already has execute permission for some user (X)"
keymon · 573 weeks and 2 days ago
What about scripts, like Sh, Bash, Perl, Python, etc?
kaedenn · 573 weeks and 2 days ago
Also, why the 3
kaedenn · 573 weeks and 2 days ago
Also, why the 3[less than] and a subshell? Wouldn't a pipe work here?
kaedenn · 573 weeks and 2 days ago
For scripts the "file" command returns this: something: a /bin/env bash script, ASCII text executable So it works. I only used the 3< you can request input in the middle, you are not changing the normal input. You can remove it: while IFS= read -r -d $'\0' file; do file "$file" | egrep -q 'executable|ELF' && echo chmod +x "$file"; done < <(find . -type f -print0) Or even: for file in $(find . -type f); do file "$file" | egrep -q 'executable|ELF' && echo chmod +x "$file"; done
keymon · 573 weeks and 1 day ago ??? ? ????? ????
seofox · 27 weeks and 3 days ago
seofox · 26 weeks and 4 days ago

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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