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Old 04-02-2012, 01:48 PM   #1
Registered: Apr 2011
Location: Philadelphia
Posts: 160

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Running if statement from command line?

Hello All,

We have some software that we use through a web browser that runs some reports by passing a command to the shell's command line.

Is it possible for me to write something like this (below) but make it into all one line to be issued on the command line...?

For example:

while (( $GREP_RETCODE != "0" ))
	ps -ef | grep -v grep | grep
	if [[ $GREP_RETCODE == 0 ]]
		exit 0
		##If NOT found sleep 1 and try the ps command again...
		sleep 1
If this doesn't make sense let me know and I'll try to clarify.

Basically what I'm trying to do is:
If the command "" is found I want to sleep for a moment and try again. If the cmd is not found in the ps -ef statement then Run the Report...

Any suggestions would be much appreciated.

Thanks in Advance,
Old 04-02-2012, 04:02 PM   #2
Registered: Sep 2003
Posts: 382

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If is possible to strings shell commands together on a single line with semicolons, like this:

for f in `ls *`; do echo "$f"; done
However, unless there is some very good reason not to, you might want to consider placing the shell commands in a file, and executing the file. If the commands I used above were intended to be executed by bash, and the commands are in the file $HOME/src/bash/my_loop.bash then:

bash $HOME/src/bash/my_loop.bash
could be used to execute the commands.
Old 04-02-2012, 04:04 PM   #3
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Assuming I made no typing errors, this should work....
GREP_RETCODE=1; while (($GREP_RETCODE != "0")); do ps -ef | grep -v grep | grep; GREP_RETCODE=$?; if [[ $GREP_RETCODE == 0 ]]; then exit 0; else sleep 1; fi; done
1 members found this post helpful.
Old 04-02-2012, 04:08 PM   #4
Registered: Apr 2011
Location: Philadelphia
Posts: 160

Original Poster
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Hey kakaka, thanks for the reply!

Yea you may be right... I was thinking of something else and I'm thinking I was a bit off base.
But that for loop on the command line is going to help me out. Thanks...

Thanks Again,
Old 04-02-2012, 04:10 PM   #5
Registered: Apr 2011
Location: Philadelphia
Posts: 160

Original Poster
Rep: Reputation: 3
Hey weibullguy, thanks for the reply too!

Cool, thanks for that... I'm thinking I'm going to have to go back and re-think what I'm going to do. (sad face)
But really, thanks for your suggestion.

Thanks Again,


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