run_when_changed

   1 #!/bin/sh
   2
   3 WATCH_FULL_FILE="$1"
   4 shift 1;
   5
   6 if ! [ -e "$WATCH_FULL_FILE" ]; then
   7     echo "No such file or directory $WATCH_FULL_FILE";
   8 fi;
   9
  10 WATCH_DIR=`dirname "$WATCH_FULL_FILE"`
  11 WATCH_FILE=`basename "$WATCH_FULL_FILE"`
  12
  13 if which inotifywait > /dev/null 2>&1; then
  14     inotifywait -m -e close_write,moved_to,create $WATCH_DIR |
  15         while read -r directory events filename; do
  16             if [ "x$filename" = "x$WATCH_FILE" ]; then
  17                 ( exec "$@" );
  18             fi;
  19         done;
  20 else
  21     CURR_TIME=$(stat -c '%Y' "$WATCH_FULL_FILE");
  22     while sleep 1; do
  23         NEW_TIME=$(stat -c '%Y' "$WATCH_FULL_FILE");
  24         if [ "x$NEW_TIME" != "x$CURR_TIME" ]; then
  25             CURR_TIME=$NEW_TIME
  26             ( exec "$@" );
  27         fi;
  28     done;
  29 fi;