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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 SUSE

igawk

IGAWK(1)							 Utility Commands							  IGAWK(1)

NAME

       igawk - gawk with include files

SYNOPSIS

       igawk [ all gawk options ] -f program-file [ -- ] file ...
       igawk [ all gawk options ] [ -- ] program-text file ...

DESCRIPTION

       Igawk is a simple shell script that adds the ability to have ``include files'' to gawk(1).

       AWK programs for igawk are the same as for gawk, except that, in addition, you may have lines like

	      @include getopt.awk

       in your program to include the file getopt.awk from either the current directory or one of the other directories in the search path.

OPTIONS

       See gawk(1) for a full description of the AWK language and the options that gawk supports.

EXAMPLES

       cat << EOF > test.awk
       @include getopt.awk

       BEGIN {
	    while (getopt(ARGC, ARGV, "am:q") != -1)
		 ...
       }
       EOF

       igawk -f test.awk

SEE ALSO

       gawk(1)

       Effective AWK Programming, Edition 1.0, published by the Free Software Foundation, 1995.

AUTHOR

       Arnold Robbins (arnold@skeeve.com).

Free Software Foundation					    Nov 3 1999								  IGAWK(1)
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