retry.sh

#!/usr/bin/env bash

PROGNAME=$(basename $0)

function usage() {
    echo "Usage: $PROGNAME [-c MAX_RETRY] [-s INTERVAL_SEC] -- COMMAND" 1>&2
    echo "  Retry a command if failed" 1>&2
    echo "" 1>&2
    echo "Options:" 1>&2
    echo "  -h, --help       Show this message" 1>&2
    echo "  -c MAX_RETRY     Number of retries (default: 3)" 1>&2
    echo "  -s INTERVAL_SEC  Interval to retry in seconds (default: 1)" 1>&2
}

MAX_RETRY=3
INTERVAL_SEC=1

while [ ${#} -gt 0 ]
do
  case $1 in
    '-h'|'--help' )
      usage
      exit 0
      ;;
    '-c' )
      MAX_RETRY="$2"
      shift 2
      ;;
    '-s' )
      INTERVAL_SEC="$2"
      shift 2
      ;;
    '--' )
      shift
      break
      ;;
    *)
      usage
      exit 1
      break
      ;;
  esac
done

RETRY_COUNT=0
until [ $RETRY_COUNT -ge $MAX_RETRY ]; do
    $@
    if [ $? -eq 0 ]; then exit 0; fi
    let ++RETRY_COUNT
    sleep $INTERVAL_SEC
    echo "[RETRY $RETRY_COUNT] Failed to execute, retry '$@'" 1>&2
done

echo "No success to execute '$@'" 1>&2
exit 1

$ ./retry.sh -c 3 -s 1 -- ls /hoge