07-17-2011
Opening a file takes time. So if possible, you should open each file only once (or the minimum number of times you can) and get everything you might need and save it in memory (in variables).
OTOH, I understand that the way Linux works now is to use all unused RAM as cache. So if you open a file, search it and close it, the whole file will stay cached in RAM until some other allocation causes it to be discarded. The result is that the second open will probably be almost instantaneous.
Of course, if you have many more files than will fit in your available RAM, then you'll lose the cache advantage.
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LEARN ABOUT REDHAT
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 17 February 2002 ZIPGREP(1L)