LDP/LDP/guide/docbook/abs-guide/recurse.sh

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#!/bin/bash
# recurse.sh
# Can a script recursively call itself?
# Yes, but is this of any practical use?
# (See the following.)
RANGE=10
MAXVAL=9
i=$RANDOM
let "i %= $RANGE" # Generate a random number between 0 and $RANGE - 1.
if [ "$i" -lt "$MAXVAL" ]
then
echo "i = $i"
./$0 # Script recursively spawns a new instance of itself.
fi # Each child script does the same, until
#+ a generated $i equals $MAXVAL.
# Using a "while" loop instead of an "if/then" test causes problems.
# Explain why.
exit 0
# Note:
# ----
# This script must have execute permission for it to work properly.
# This is the case even if it is invoked by an "sh" command.
# Explain why.