Sponsored Content
Top Forums UNIX for Beginners Questions & Answers Shell Script behaviour and syntax Post 303045796 by Cybora on Monday 13th of April 2020 03:45:46 PM
Old 04-13-2020
Shell Script behaviour and syntax

Here are the 3 scripts(FirstScrpt.sh,firstcallScrpt.sh,startProcess.sh) that were running in the server for the past several years.
I understand the way it is written is that for every 1 hour 'firstcallScript.sh' is being called in that it kills the pid of 'startProcess.sh'
and starts again.

2 things I noticed
1. Value of pid.txt never changes if it is being is killed and created every hour.
2. It never runs in the background even when it is run with '&' like (./FirstScrpt.sh &)

FirstScrpt.sh
Code:
#!/bin/bash

if [ $# -ne 1 ]
then
	echo "Usage:  $0 test|prod"
	exit 1
fi
envRun=$1

  echo "Level is :  ${envRun}"
	while [ 1 ]
	do
	cat pid.txt | xargs -l1 kill
	./firstcallScript.sh ${envRun}
	sleep 3600
	done

firstCallScript.sh
Code:
#!/bin/bash

if [ $# -ne 1 ]
then
	echo "Usage:  $0 test|prod"
	exit 1
fi
envRun=$1

if [ $envRun = "test" ] 
then
  echo "Level is  :  ${envRun}"
     ./startProcess.sh ${envRun}
   
 else
   echo "Level is test Invoke test script :  ${envRun}"
   	./startProcess.sh ${envRun}
	
fi

startProcess.sh

Code:
#!/bin/bash 
envRun=$1
echo "${envRun}"
echo "I'm a Linux user."
echo $! > pid.txt


Last edited by Cybora; 04-13-2020 at 04:53 PM.. Reason: Edited the firstScript for 1 hour of sleep
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

any explanation for thsi shell script behaviour

hello whats the difference between excuting a shell script as a)sh myscript.sh b). ./myscript.sh i noticed that my shell script works fine when i run it as . ./myscript .sh but fails when i run it as sh myscript.sh could anybody explain why. the shell script is very simple ... (9 Replies)
Discussion started by: xiamin
9 Replies

2. Shell Programming and Scripting

Shell script syntax checker

I have a rather big script that i have written in ksh and it is falling over in two places with a 'test argument' error. I know this usually means that the if statement is not correct, but it is fine. I have looked through the rest of the script for any odd brackets or ` marks, but can't see... (2 Replies)
Discussion started by: handak9
2 Replies

3. Shell Programming and Scripting

Basic Shell script syntax help

Hi All, I am new to shell scripting. I have a variable which holds a numeric value.I have to check whether this variable holds a value between(0- 8),(8-17)(17-24).How do i write this syntax using if in shell scripting. Thanks Vignesh (2 Replies)
Discussion started by: vignesh53
2 Replies

4. Shell Programming and Scripting

How to Check Shell script syntax w/o executing

Hello All, I looking for a way to verify the correction of shell script syntax. Is there any switch like -c in perl which do this in shell ? Thank You. (1 Reply)
Discussion started by: Alalush
1 Replies

5. Shell Programming and Scripting

Help Syntax Shell-Script

Hi Guys, iīve a question ... but itīs a litte bit tricky: iīve a 3 php-scripts which runīs via cron at night. These script reads an xml-file a writes it in an MySQL-DB. I named them (for example here ) Script1 - Script3. The XML-Files i named xml1 - xml3. Now, iīve build a Batch-file,... (10 Replies)
Discussion started by: jackcracker
10 Replies

6. Shell Programming and Scripting

Syntax error calling TCL script from shell script

hello everyone i am beginner on shell scripting .and i am working on my project work on ad hoc network i wrote a batch (.sh) to do a looping and execute a tcl script i wrote before in each iteration ..but i got this problem " syntax error near unexpected token `('... (1 Reply)
Discussion started by: marcoss90
1 Replies

7. Shell Programming and Scripting

shell script | bc syntax format

sorry but need help http://i.investopedia.com/inv/articles/site/CalculationEMA.gif trying to achieve ema in script I have this syntax which errors ema=` ; the 0.153846154 ='s Smoothing Factor really appreciate help (3 Replies)
Discussion started by: harte
3 Replies

8. Shell Programming and Scripting

syntax error in shell script

I am creating a shell script. In which, I need to get server name and server IP. I used this command in script. servername=`cat /etc/hosts|grep `eval hostname`|awk '{print $2}'` however, when execute script or put set -x to debug, it return: line 13: syntax error at line 13: `|' unexpected... (4 Replies)
Discussion started by: duke0001
4 Replies

9. Shell Programming and Scripting

Bash syntax behaviour : [[ vs [

Hello. In the following : RESTORE_FF contain a file name : a_file.tar.gz I am testing in a directory if "a_file.tar.gz" exists and or if any file like "a_file.tar.gz" exists. So "a_file.tar.gz" will give me file exists So "a_file.tar.gz." will give me file exists So... (5 Replies)
Discussion started by: jcdole
5 Replies

10. Shell Programming and Scripting

Help with if statement syntax in shell script

I want to make the file test condition a variable ($Prmshn in code below). My goal is to use something like the first three unsuccessful if statetments since the 'if #!/bin/ksh test_input() { Prmshn=${1} InFLNm=${2} ifReq="-$Prmshn $InFLNm" #the following three if statments fail: #if ] ;... (10 Replies)
Discussion started by: ms63707
10 Replies
echo(1B)					     SunOS/BSD Compatibility Package Commands						  echo(1B)

NAME
echo - echo arguments to standard output SYNOPSIS
/usr/ucb/echo [-n] [argument] DESCRIPTION
echo writes its arguments, separated by BLANKs and terminated by a NEWLINE, to the standard output. echo is useful for producing diagnostics in command files and for sending known data into a pipe, and for displaying the contents of envi- ronment variables. For example, you can use echo to determine how many subdirectories below the root directory (/) is your current directory, as follows: o echo your current-working-directory's full pathname o pipe the output through tr to translate the path's embedded slash-characters into space-characters o pipe that output through wc -w for a count of the names in your path. example% /usr/bin/echo "echo $PWD | tr '/' ' ' | wc -w" See tr(1) and wc(1) for their functionality. The shells csh(1), ksh(1), and sh(1), each have an echo built-in command, which, by default, will have precedence, and will be invoked if the user calls echo without a full pathname. /usr/ucb/echo and csh's echo() have an -n option, but do not understand back-slashed escape characters. sh's echo(), ksh's echo(), and /usr/bin/echo, on the other hand, understand the black-slashed escape characters, and ksh's echo() also understands a as the audible bell character; however, these commands do not have an -n option. OPTIONS
-n Do not add the NEWLINE to the output. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWscpu | +-----------------------------+-----------------------------+ SEE ALSO
csh(1), echo(1), ksh(1), sh(1), tr(1), wc(1), attributes(5) NOTES
The -n option is a transition aid for BSD applications, and may not be supported in future releases. SunOS 5.10 3 Aug 1994 echo(1B)
All times are GMT -4. The time now is 01:28 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy