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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 They are outdated and only there for backwards compatibility with other outdated software.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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LEARN ABOUT DEBIAN

setmaillist

setmaillist(1)						      General Commands Manual						    setmaillist(1)

NAME

       setmaillist - create a binary mailing list

SYNOPSIS

       setmaillist bin tmp

DESCRIPTION

       setmaillist reads a mailing list from its standard input.

       setmaillist writes the mailing list in a binary format to tmp; it then moves tmp to bin.  tmp and bin must be on the same filesystem.

       If there is a problem creating tmp, setmaillist complains and leaves bin alone.

       The binary mailing list format is portable across machines.

       setmaillist always creates bin world-readable.

MAILING LIST FORMAT

       The mailing list read by setmaillist is a series of lines.  NUL bytes are not allowed.

       If a line begins with a dot or slash, setmaillist takes the entire line as an include file name.

       If  a line begins with an ampersand, setmaillist takes the rest of the line as a recipient address.  If a line begins with a letter or num-
       ber, setmaillist takes the entire line as a recipient address.  Each recipient address must include a fully qualified domain name.  Recipi-
       ent addresses longer than 800 bytes are not allowed.

       setmaillist ignores blank lines and lines beginning with #.  It also ignores spaces and tabs at the ends of lines.

       For example,

	  god@heaven.af.mil
	  djb@silverton.berkeley.edu

       is a mailing list with two addresses.

SEE ALSO

       setforward(1), newinclude(1), printmaillist(1)

																    setmaillist(1)
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