mdwsetup.py (progoutput): Only read one byte to decide whether there is more.

There's no point in slurping the entire output now that we're closing
the pipe /before/ trying to waitpid(2): the child will hit `SIGPIPE' (or
`EPIPE') rather than blocking on output.

diff --git a/mdwsetup.py b/mdwsetup.py
index 57832a2..0210714 100644 (file)
--- a/mdwsetup.py
+++ b/mdwsetup.py
@@ -76,7 +76,7 @@ def progoutput(command):
   kid = SUB.Popen(command, stdout = SUB.PIPE)
   try:
     out = kid.stdout.readline()
-    junk = kid.stdout.read()
+    junk = kid.stdout.read(1)
   finally:
     kid.stdout.close()
   if junk != '': raise ValueError \