I am not able to understand how we can use < and > signs for string comparison....????
According to the standards, you can't with test... and [ ... ],
but in [[ ... ]], < and > are string comparison operators. The -lt and -gt operators perform numeric comparisons in all three forms of these testing methods.
In bash, the < and > are string comparisons in test ... and [ ... ]. In ksh, the < and > will be treated as redirection operators, not string comparisons. I.e., in ksh:
will print gt because 100 is not an empty string and will create a file named 200 because > is a redirection operator. But in bash, this same code will print not gt and will not create a file. Both of these behaviors conform to the standards because the standards don't specify any meaning for < and > in these two cases.
=================
I take part of this back. Despite what the bash man page says, at least on Mac OS X, bash and ksh both treat < and > as redirection operators in test and [.
Last edited by Don Cragun; 09-13-2012 at 06:40 AM..
Reason: Update based on testing bash on OS X Lion
This User Gave Thanks to Don Cragun For This Post:
Hi all,
I got some problems on executing the following scripts.
Scripts:
if ]; then
echo "M${str}O 0 1" >> ${tempFile}
elif ]; then
echo "M${str}O 1 0" >> ${tempFile}
else
echo "M${str}O 0 0" >> ${tempFile}
fi
Error:
"`;' is not expected."
what's the problem? (2 Replies)
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NUM=$1... (4 Replies)
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echo -n "enter variable (a, b, or c): "
read freq
if ;
then echo "a"
elif ;... (2 Replies)
Script Gurus,
Need your help in getting this script to come out of logical error : I have pasted the script below: This script finds disk utilzation ... the script is written for both AIX and SUN OS... and option will be given in the initial to select DB or Non DB... its required for my prj...... (1 Reply)
I am getting below error from this code (which is at line 24):
if ] #this is line24 in code
then
mv $File_source_path/$File_name $File_name'_'`date '+%d%m%y'`
Error:
line 24:
Any help with the syntax. I am putting 2 condition with 'AND' clause.
This is bash shell. (2 Replies)
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Use and complete the template provided. The entire template must be completed. If you don't, your post may be deleted!
1. The problem statement, all variables and given/known data:
This is my problem for the class.
Write a script that asks for the user's age. If it is equal to or higher... (6 Replies)
Hi all,i have configured the following script to check if the file exists or not,
#!/bin/sh
sleep 30
{
FILEFULL=$1`date +$2`*
if ;
then
echo $FILEFULL exist
else
echo "$FILEFULL File not Found" | mail -s 'server' myaccount@mydomain.com
fi
}
but i have a problem, i need to... (2 Replies)
Hello all,
I have a scenario where I take user input values and accordingly take actions
say I run a script with
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Now for second the scenario is
if
then
echo... (3 Replies)
Hello experts,
I am having problems with ELIF.
Please see the below code :
read a;
read b;
read c;
if || || ; then
echo "EQUILATERAL"
elif || || ; then
echo "SCALENE"
else
echo "ISOSCELES"
fi
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