wait: fix support for wait -1

Only on unix systems. Does waitpid(-1, ...) to wait for any child
process to exit.

Signed-off-by: Steve Bennett <steveb@workware.net.au>

1 files changed, 6 insertions, 0 deletions

diff --git a/jim-exec.c b/jim-exec.c
index 74a4d18..be18fbb 100644
--- a/jim-exec.c
+++ b/jim-exec.c
@@ -614,6 +614,12 @@ static int Jim_WaitCommand(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
     if (phandle == JIM_BAD_PHANDLE) {
         pid = -1;
     }
+    else if (pid < 0) {
+        /* This catches the case where pid=-1. It is only supported on unix where
+         * the returned phandle is a pid, so can simply assign here
+         */
+        pid = phandle;
+    }
 
     errCodeObj = JimMakeErrorCode(interp, pid, status, NULL);