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Setting "default" positional parameters (in bash)

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# 1  
Old 06-18-2009
Setting "default" positional parameters (in bash)
Hi,

I have a script that processes the positional parameters provided on the command line, or - if none are provided - uses some defaults instead.

I've currently got it written as follows, which works like a charm, but I was wondering if there is a different/other/better/... way of doing this?

Code:
#!/bin/sh

[ $# -eq 0 ] && set -- foo bar blegga

for arg do
    echo ${arg}
done

Thanks,

PVDB
# 2  
Old 06-18-2009
something like..

Code:
if [ $# -eq 0 ];then
echo "usage : $0 arg1"
exit
fi
arg1=$1
if [ $arg1 -eq "" ]; then
arg1=default
fi

Last edited by clx; 06-18-2009 at 03:15 PM.. Reason: removed "something like.." from code tags
# 3  
Old 06-18-2009
Code:
#!/bin/ksh
first="${1:-foo}"
second="${2:-bar}"

echo "\$1->[${first}] \$2->[${second}]"

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