Don't show formatting progress bar after mkfs has exited.

mke2fs will finish it's work quickly, and anaconda will spend quite
sometime reading in the output, and updating the progress dialog in
certain cases - the attached patch adds a check to the read/progress
loop to check to see if the process has finished, and jumps out early
if that's the case.

1 files changed, 12 insertions, 1 deletions

diff --git a/iutil.py b/iutil.py
index 49509e993..ec25adba4 100644
--- a/iutil.py
+++ b/iutil.py
@@ -236,11 +236,22 @@ def execWithPulseProgress(command, argv, stdin = None, stdout = None,
         runningLog.write(s)
         if progress: progress.pulse()
 
+        # break out early if the sub-process changes status.
+        # no need to flush the stream if the process has exited
+        try:
+            (pid, status) = os.waitpid(childpid,os.WNOHANG)
+            if pid != 0:
+                break
+        except OSError as e:
+            log.critical("exception from waitpid: %s %s" %(e.errno, e.strerror))
+
         if len(s) < 1:
             break
 
     try:
-        (pid, status) = os.waitpid(childpid, 0)
+        #if we didn't already get our child's exit status above, do so now.
+        if not pid:
+            (pid, status) = os.waitpid(childpid, 0)
     except OSError as e:
         log.critical("exception from waitpid: %s %s" %(e.errno, e.strerror))