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Full Discussion: Assistence With Using Asterisks in GREP Expressions
Top Forums Shell Programming and Scripting Assistence With Using Asterisks in GREP Expressions Post 302336382 by MagusScythe on Wednesday 22nd of July 2009 03:20:30 AM
Old 07-22-2009
Quote:
Originally Posted by ryandegreat25
from what i know when were dealing with asterisk(*) char in a line we need to use double qoutes. This evaluates the "middle *" (.*) and use escape character on both the first character (^) and last character ($).

Code:
-bash-3.2$ cat test
*ryan*
*you
*me*
-bash-3.2$ cat test | grep "^\*.*\*$"
*ryan*
*me*
-bash-3.2$

Quote:
Originally Posted by ranjithpr
Hop this is what you are looking for

Code:
sh-3.2$ cat f1
word1 word2 *word3* word4
word5 *word6*
*word7* word8* *word9*

sh-3.2$ grep -ow "*[^*]*\*" f1
*word3*
*word6*
*word7*
*word9*
sh-3.2$

I tried both - neither worked.

\<.*\> returns everything, as would be expected.

\<\*.*\> , however, doesn't return words that start with an asterisk. I think it's choking on asterisks for some reason. It doesn't make a difference if instead of escaping the asterisk, I put it in single or double quotes, like so:

\<'*'.*\>

\<"*".*\>

Can an asterisk not be legitimately part of a "word" - as defined by GREP? I figured a word was simply any string with spaces or tabs around it.
 

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LEARN ABOUT REDHAT

pidof

PIDOF(8)						Linux System Administrator's Manual						  PIDOF(8)

NAME

       pidof -- find the process ID of a running program.

SYNOPSIS

       pidof [-s] [-x] [-o omitpid] [-o omitpid..]  program [program..]

DESCRIPTION

       Pidof  finds  the  process  id's (pids) of the named programs. It prints those id's on the standard output. This program is on some systems
       used in run-level change scripts, especially when the system has a System-V like rc structure. In that case these scripts  are  located	in
       /etc/rc?.d, where ? is the runlevel. If the system has a start-stop-daemon (8) program that should be used instead.

OPTIONS

       -s     Single shot - this instructs the program to only return one pid.

       -x     Scripts too - this causes the program to also return process id's of shells running the named scripts.

       -o     Tells  pidof  to omit processes with that process id. The special pid %PPID can be used to name the parent process of the pidof pro-
	      gram, in other words the calling shell or shell script.

NOTES

       pidof is simply a (symbolic) link to the killall5 program, which should also be located in /sbin.

       When pidof is invoked with a full pathname to the program it should find the pid of, it is reasonably safe. Otherwise it is  possible  that
       it returns pids of running programs that happen to have the same name as the program you're after but are actually other programs.

SEE ALSO

       shutdown(8), init(8), halt(8), reboot(8)

AUTHOR

       Miquel van Smoorenburg, miquels@cistron.nl

								    01 Sep 1998 							  PIDOF(8)
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