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Full Discussion: egrep is very slow : How to improve performance
Top Forums Shell Programming and Scripting egrep is very slow : How to improve performance Post 302166538 by vino on Tuesday 12th of February 2008 05:50:26 AM
Old 02-12-2008
Quote:
Originally Posted by hidnana
I have uploaded the $key as a screenshot as I don't have the text version right now..., it's a big string concatenated by "|".

Can you pls. tell me which is better than egrep....
grep.. perl... sed...?
And why should egrep take around 50..60 seconds in an iteration ...?
And will splitting the ${PICKUP_DIR}/new_update file into multiple files and searching each file until a match is found, help in anyway...?
Are the keys separated by a '|' ? Or is the whole thing a key in itself ?

If the keys are separated by '|', then change the file such that each key is on a new line. Then
Code:
egrep -f key.txt ${PICKUP_DIR}/new_update

I dont know if you will have any advantage in splitting up the file.
 

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LEARN ABOUT NETBSD

zfgrep

ZGREP(1)						    BSD General Commands Manual 						  ZGREP(1)

NAME

     zgrep, zegrep, zfgrep -- print lines matching a pattern in gzip-compressed files

SYNOPSIS

     zgrep [grep-flags] [--] pattern [files ...]

     zegrep [grep-flags] [--] pattern [file ...]

     zfgrep [grep-flags] [--] pattern [file ...]

DESCRIPTION

     zgrep runs grep(1) on files or stdin, if no files argument is given, after decompressing them with zcat(1).

     The grep-flags and pattern arguments are passed on to grep(1).  If an -e flag is found in the grep-flags, zgrep will not look for a pattern
     argument.

     zegrep calls egrep(1), while zfgrep calls fgrep(1).

EXIT STATUS

     In case of missing arguments or missing pattern, 1 will be returned, otherwise 0.

SEE ALSO

     egrep(1), fgrep(1), grep(1), gzip(1), zcat(1)

AUTHORS

     Thomas Klausner <wiz@NetBSD.org>

BSD
								 December 28, 2003							       BSD
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