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Full Discussion: For loop in process each file
Top Forums UNIX for Dummies Questions & Answers For loop in process each file Post 302943837 by bakunin on Wednesday 13th of May 2015 08:53:06 AM
Old 05-13-2015
In addition to what sea said (and to what i wholeheartedly agree):

1) do not use "open-ended" for-loops, because they can have side-effects. Something like (you are effectively doing the same)

Code:
for VAR in <list of filenames> ; do
     do_something_with "$VAR"
done

will work with several or several hundreds of files but might break with a "too many arguments"-error or a "input line too long"-error with several thousands of files. Do a

Code:
ls -1 | grep <some-filter-criteria> |\
while read VAR ; do
     do_something_with "$VAR"
done

instead. This will work with even the biggest amount of files.

2) Never, NEVER use backticks any more. They are outdated and only there for backwards compatibility with other outdated software. Use the POSIX-compliant

Code:
$(command | command2 | .... )

instead.

Btw.: i am not sure what you are trying to do but to me this seems to be a search for symbolic links. This can more easily be done by:

Code:
find /start/dir -type l -print

see the man page for "find" for details.



I hope this helps.

bakunin
 

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