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Full Discussion: Speeding up a Shell Script (find, grep and a for loop)
Top Forums UNIX for Dummies Questions & Answers Speeding up a Shell Script (find, grep and a for loop) Post 302222037 by era on Wednesday 6th of August 2008 01:00:26 AM
Old 08-06-2008
I don't understand the construction set | grep $value /tmp/date.out -- as far as I can tell, the output from set will not be used for anything.

Also, the conditional is a Useless Use of Test, and it will print to stdout any matches; I imagine that's undesirable. The following avoids those problems.

Code:
if ! grep "$value" /tmp/dave.out >/dev/null
then
  echo "$value"" >>/tmp/dave_files.out
fi

Still, if you had your list of PDF files in another file, one PDF per line, it could be as simple as

Code:
fgrep -vxf pdfs.txt /tmp/dave.out >/tmp/dave_files.out

The use of fgrep -x requires an exact match (not a regex match; you know that dot in a regex matches any character, for example) spanning the whole line (that's the -x). The -v causes only lines in /tmp/dave.out which are not anywhere in pdfs.txt to be printed.
 

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LEARN ABOUT DEBIAN

i-ls

i-ls(1) 						      General Commands Manual							   i-ls(1)

NAME

       i-ls - display file stat and checksum information for files

SYNOPSIS

       i-ls [-s] filename

       i-ls [-s] dirname

       Specify a filename for i-ls to examine, or specify a directory with dirname to examine all the files in the directory.

       -s

	      Do not show/calculate checksums for all regular files.

DESCRIPTION

       The integrit system detects intrusion by detecting when trusted files have been altered.

       integrit records information about files in a database.	i-ls allows the user to see that information for live files.

       The output syntax is the same as that of integrit.

EXAMPLES

	    i-ls /tmp/foo.txt

       shows file stat attributes for the file, "/tmp/foo.txt".

	    i-ls /tmp

       shows file stat attributes for all files in the directory, "/tmp".

	    i-ls -s /tmp

       shows file stat attributes for all files in the directory, "/tmp", also including also checksums for all regular files.

AUTHOR

       Ed L Cashin <ecashin@users.sourceforge.net>

       See the integrit web site for up to date releases and information at

	   http://integrit.sourceforge.net/

SEE ALSO

       Integrit File Verification System Manual (info), lstat(2)

Version 4.1							   Jul 27, 2001 							   i-ls(1)
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