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Top Forums Shell Programming and Scripting Better and efficient way to reverse search a file for first matched line number. Post 302562434 by kchinnam on Thursday 6th of October 2011 11:19:48 PM
Old 10-07-2011
Better and efficient way to reverse search a file for first matched line number.

How to reverse search for a matched string in a file. Get line# of the first matched line. I am getting '2' into 'lineNum' variable.

But it feels like I am using too many commands. Is there a better more efficiant way to do this on Unix?

abc.log
Code:
 
aaaaaaaaaaaaa
bbbbbbbbbbbbb
ccccccccccccc
aa Started aa
ddddddddddddd

Code:
 
vStart='Started'; myLog=abc.log
lineNum=`/usr/xpg4/bin/tail -r $myLog | cat -n | sed -n "/$vStart/{p;q;}" | awk '{print $1}'`

 

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AUSEARCH_ADD_REGEX(3)						  Linux Audit API					     AUSEARCH_ADD_REGEX(3)

NAME
ausearch_add_regex - use regular expression search rule SYNOPSIS
#include <auparse.h> int ausearch_add_regex(auparse_state_t *au, const char *expr); DESCRIPTION
ausearch_add_regex adds one search condition based on a regular expression to the current audit search expression. The search conditions can then be used to scan logs, files, or buffers for something of interest. The regular expression follows the posix extended regular expression conventions, and is matched against the full record (without interpreting field values). If an existing search expression E is already defined, this function replaces it by (E && this_regexp). RETURN VALUE
Returns -1 if an error occurs; otherwise, 0 for success. SEE ALSO
ausearch_add_expression(3), ausearch_add_item(3), ausearch_clear(3), ausearch_next_event(3), regcomp(3). AUTHOR
Steve Grubb Red Hat Sept 2007 AUSEARCH_ADD_REGEX(3)
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