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Shell Programming and Scripting

Need explanation for the syntax(code)

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# 1  
Old 03-21-2007
Java Need explanation for the syntax(code)
Hi I am new to shell script programming...
want to know the process of the following:

if[ -n "$MISSINGOPTARG"]
then
echo "$0: missing argument for option(s) :$MISSINGOPTARG"
echo "usage" $USAGE"
exit 1
fi
# 2  
Old 03-21-2007
Quote:
Originally Posted by chandhar
Hi I am new to shell script programming...
want to know the process of the following:

if[ -n "$MISSINGOPTARG"]
then
echo "$0: missing argument for option(s) :$MISSINGOPTARG"
echo "usage" $USAGE"
exit 1
fi
-n "$MISSINGOPTARG"
-n option checks whether $MISSINGOPTARG contain any text in it.

You have to use -z option to check whether $MISSINGOPTARG is empty and if it is empty then condition -z "$MISSINGOPTARG" is true
Code:
if[ -z "$MISSINGOPTARG" ]
then
   echo "$0: missing argument for option(s) :$MISSINGOPTARG"
   echo "usage" $USAGE"
   exit 1
fi

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