X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?p=pintos-anon;a=blobdiff_plain;f=src%2Futils%2Fpintos;h=156421649d943356fe69e2447e55a307bf84fd91;hp=eca4708516e41f3c715d2145e761ba775036ed6a;hb=161bf03beb0aae6ad38aa884cd534a94737d396a;hpb=cbf1fae30fd49b3d2495b60ebd53d4c8b919acf1

diff --git a/src/utils/pintos b/src/utils/pintos
index eca4708..1564216 100755
--- a/src/utils/pintos
+++ b/src/utils/pintos
@@ -827,8 +827,8 @@ sub xsystem {
 
 		# Read and print out pipe data.
 		my ($len) = length ($buf);
-		waitpid ($pid, 0), last
-		  if sysread ($in, $buf, 4096, $len) <= 0;
+		my ($n_read) = sysread ($in, $buf, 4096, $len);
+		waitpid ($pid, 0), last if !defined ($n_read) || $n_read <= 0;
 		print substr ($buf, $len);
 
 		# Remove full lines from $buf and scan them for keywords.