MINOR: zsync: Add quiet option normally ment to be used with check mode

Author: julthomas

zsync/zsync

@@ -57,6 +57,7 @@ Options:
     -i, --include   Add include rule
     -e, --exclude   Add exclude rule
     -t, --check     Check mode, implies dry-run
+    -q, --quiet     Disable stdout, repeat for stderr
     -h, --help      Display this help
 
 Current configuration file: $CONFIG
@@ -73,7 +74,9 @@ Check mode is ment to be used from scripts to test if peers are
 in sync. In check mode, status codes are as follows:
     0: peers in sync
     1: peers out of sync
-    2: error, sync status is undefined
+    2: error, sync status is undefined or fatal error
+
+Flag -q, --quiet is normally ment to be used with check mode.
 "
     exit "$status"
 }
@@ -90,7 +93,7 @@ function info() {
 
 function fatal() {
     info --${FUNCNAME[0]} "$@"
-    exit 1
+    exit 2
 }
 
 function error() {
@@ -322,6 +325,7 @@ argv=( "$@" )
 XDEBUG=
 DIFF=
 CHECK=
+QUIET=0
 
 while (( $# > 0 )); do
     case "$1" in
@@ -337,6 +341,7 @@ while (( $# > 0 )); do
         --do-rsync)  do_remote_rsync "${@:2}"; exit $? ;;
         --do-keyscan) keyscan=1 ;;
         --x-debug) XDEBUG=1 ;;
+        -q|--quiet) (( QUIET++ )) ;;
         -h|--help) exit_usage ;;
         --) shift; break ;;
         -*) exit_usage 1 ;;
@@ -348,6 +353,8 @@ done
 includes+=( "$@" )
 
 [[ -n $XDEBUG ]] && set -x
+(( QUIET >= 1 )) && exec 1>/dev/null
+(( QUIET >= 2 )) && exec 2>/dev/null
 
 trap on_exit EXIT
 
@@ -415,7 +422,7 @@ if [[ -n $CHECK ]]; then
     case "$retval,${#CHECK_OUT_OF_SYNC[@]}" in
         0,0) exit 0 ;;
         0,*) exit 1 ;;
-        *) exit 2 ;;
+        *) exit 2 ;; # same as fatal
     esac
 fi
 exit "$retval"