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Full Discussion: How to speed up grep?
Top Forums Shell Programming and Scripting How to speed up grep? Post 302375108 by methyl on Thursday 26th of November 2009 01:36:05 PM
Old 11-26-2009
Not sure of your exact requirement - particularly whether there are dependencies. The "egrep" command can search for multiple messages in one pass.

Code:
ls -1tr logfile* | while read FILENAME
do
    egrep -i "message 1|message 2|message 3|message 4" "${FILENAME}"
done

I sometimes use "egrep" to eliminate known good messages ( egrep -iv ) and then only look at the exceptions.

Unless you only look at the logs every 10 days there is little point in reading old logs a second time unless the search criteria changes after the event.
 

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LEARN ABOUT MOJAVE

zipgrep

ZIPGREP(1L)															       ZIPGREP(1L)

NAME

       zipgrep - search files in a ZIP archive for lines matching a pattern

SYNOPSIS

       zipgrep [egrep_options] pattern file[.zip] [file(s) ...]  [-x xfile(s) ...]

DESCRIPTION

       zipgrep	will  search  files  within  a ZIP archive for lines matching the given string or pattern.  zipgrep is a shell script and requires
       egrep(1) and unzip(1L) to function.  Its output is identical to that of egrep(1).

ARGUMENTS

       pattern
	      The pattern to be located within a ZIP archive.  Any string or regular expression accepted by egrep(1) may be used.  file[.zip] Path
	      of  the  ZIP archive.  (Wildcard expressions for the ZIP archive name are not supported.)  If the literal filename is not found, the
	      suffix .zip is appended.	Note that self-extracting ZIP files are supported, as with any other ZIP archive; just	specify  the  .exe
	      suffix (if any) explicitly.

       [file(s)]
	      An  optional list of archive members to be processed, separated by spaces.  If no member files are specified, all members of the ZIP
	      archive are searched.  Regular expressions (wildcards) may be used to match multiple members:

	      *      matches a sequence of 0 or more characters

	      ?      matches exactly 1 character

	      [...]  matches any single character found inside the brackets; ranges are specified by a beginning character, a hyphen, and an  end-
		     ing character.  If an exclamation point or a caret (`!' or `^') follows the left bracket, then the range of characters within
		     the brackets is complemented (that is, anything except the characters inside the brackets is considered a match).

	      (Be sure to quote any character that might otherwise be interpreted or modified by the operating system.)

       [-x xfile(s)]
	      An optional list of archive members to be excluded from processing.  Since wildcard characters  match  directory	separators  (`/'),
	      this  option  may  be used to exclude any files that are in subdirectories.  For example, ``zipgrep grumpy foo *.[ch] -x */*'' would
	      search for the string ``grumpy'' in all C source files in the main directory of the ``foo'' archive, but none in any subdirectories.
	      Without the -x option, all C source files in all directories within the zipfile would be searched.

OPTIONS

       All options prior to the ZIP archive filename are passed to egrep(1).

SEE ALSO

       egrep(1), unzip(1L), zip(1L), funzip(1L), zipcloak(1L), zipinfo(1L), zipnote(1L), zipsplit(1L)

URL

       The Info-ZIP home page is currently at
       http://www.info-zip.org/pub/infozip/
       or
       ftp://ftp.info-zip.org/pub/infozip/ .

AUTHORS

       zipgrep was written by Jean-loup Gailly.

Info-ZIP							   20 April 2009						       ZIPGREP(1L)
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