Shell Programming and Scripting

#!/bin/sh 

if [ -d $1 ] ; then
        echo $1
else
        echo "Usage:`basename $0` dir"
fi

echo "The end of the script."

[benjo@hp tmp]$ ./test /tmp/
/tmp/
The end of the script.

[benjo@hp tmp]$ ./test 

The end of the script.
[benjo@hp tmp]$

#!/usr/bin/ksh93

CMD=$(basename $0)
USAGE="Usage: $CMD dir"

[[ $# < 1 ]] && {
    print $USAGE
    exit 1
}

[[ -d $1 ]] || {
    print "ERROR: $1 is not a directory"
    print $USAGE
    exit 2
}

print "Directory: $1"

exit 0

#!/bin/sh
CMD=$(basename $0)
USAGE="Usage: $CMD dir"

if [ $# -lt 1 ]; then
    printf "%s\n" "$USAGE"
    exit 1
elif [ -d $1 ]; then
    echo "Directory: $1"
    exit 0
else
    printf "%s\n%s\n" \
    "ERROR: $1 is not a directory" \
    "$USAGE"
    exit 2
fi