Imported from ../bash-2.0.tar.gz.

examples/scripts.v2/repeat

@@ -0,0 +1,119 @@
+#! /bin/bash
+#
+# original from:
+# repeat: repeat a command.
+# @(#) repeat.ksh 1.1 93/06/03
+# 90/05 john h. dubois iii (john@armory.com)
+# 90/11 added help
+# 93/06/03 Added s, h, p, and v options
+#
+# conversion to bash v2 syntax done by Chet Ramey
+
+istrue()
+{
+	test 0 -ne "$1"
+}
+
+isfalse()
+{
+	test 0 -eq "$1"
+}
+
+phelp()
+{
+echo "$name: repeatedly execute a command line.
+$Usage
+commandline is executed once for each integer from startcount through endcount
+inclusive.  The default for startcount is 1 if a positive endcount or no
+endcount is given, and -1 if a negative endcount is given.  A count
+parameter consisting of a single number is taken to be an endcount.  If
+only an endcount is given and it is positive, commandline is executed
+endcount times.  endcount may be less than startcount.  If no endcount is
+given (e.g. a count parameter of \"10-\"), commandline execution repeats
+indefinitely with the iteration variable incrementing in a positive
+direction.  A count parameter of consisting of \"-\" will repeat
+indefinitely starting with 1.
+
+Note that quoting and variables in commandline are interpreted twice, once
+when it is passed to the repeat command, and once when it is actually executed.
+
+The iteration variable is \"count\".  If \$count is used in commandline, make
+sure it is quoted with ' or \.
+
+Options:
+-h: Print this help.
+-p: Print value of iteration variable on stderr before each iteration.
+-s <sec>: sleep for <sec> seconds after each iteration except the last.
+-v: Print start and end values before beginning."
+}
+
+name=${0##*/}
+Usage="Usage: repeat [-hpv] [-s <sec>] [[startcount]-][endcount] command [arg ...]"
+
+typeset -i count=1 forever=0 sleep=0 print=0 verbose=0
+
+while getopts :0123456789hpvs: opt; do
+    case $opt in
+    h) phelp; exit 0;;
+    s) sleep=$OPTARG || exit 1;;
+    p) print=1;;
+    v)verbose=1;;
+    [0-9]) break;;
+    +?) echo "$name: options should not be preceded by a '+'." 1>&2; exit 2;;
+    ?)  echo "$name: $OPTARG: bad option.  Use -h for help." 1>&2; exit 2;;
+    esac
+done
+ 
+# remove args that were options
+shift $((OPTIND-1))
+
+if [ $# -lt 2 ]; then
+    echo -e "$Usage\nUse -h for help." 1>&2
+    exit 2
+fi
+
+case "$1" in
+-[0-9]*-|[0-9]*-)
+    # Start value only
+    count=${1%-}
+    forever=1
+    ;;
+-[0-9]*-[0-9]*|[0-9]*-[0-9]*)
+    # Start and end value
+    s=${1%-}
+    end=${s##[0-9]*-}
+    count=${s%-$end}
+    ;;
+-[0-9]*|[0-9]*)
+    end=$1
+    case "$end" in
+    -\*)	count=-1;;
+    esac
+    ;;
+-)
+    forever=1
+    ;;
+*) 
+    echo "$name: bad count parameter: $1" 1>&2
+    exit 1
+    ;;
+esac
+
+shift
+
+[ -z "$end" -o $count -le "$end" ] && increment=1 || increment=-1
+
+istrue $verbose && echo "start=$count end=$end" 1>&2
+
+# Need to do this here so that up to this point, -0 will keep the leading -
+# and end will not be 0 if no value assigned
+typeset -i end
+
+let end+=increment	# make loop inclusive of original endcount
+
+while istrue $forever || [ $count -ne $end ]; do
+    istrue $print && echo $count 1>&2
+    eval "$@"
+    istrue $sleep && sleep $sleep
+    let count+=increment
+done