From b652330f2a0fcae98a54d0a9044b9c4b2d4c872f Mon Sep 17 00:00:00 2001
From: Henrik Levkowetz <henrik@levkowetz.com>
Date: Sat, 6 Nov 2010 05:24:02 +0000
Subject: [PATCH] Utility function to execute external functions.  - Legacy-Id:
 2606

---
 ietf/utils/pipe.py | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)
 create mode 100644 ietf/utils/pipe.py

diff --git a/ietf/utils/pipe.py b/ietf/utils/pipe.py
new file mode 100644
index 000000000..a82a2aab9
--- /dev/null
+++ b/ietf/utils/pipe.py
@@ -0,0 +1,30 @@
+# Simplified interface to os.popen3()
+
+def pipe(cmd, str=None):
+    from popen2 import Popen3 as Popen
+    bufsize = 4096
+    MAX = 65536*16
+
+    if str and len(str) > 4096:                 # XXX: Hardcoded Linux 2.4, 2.6 pipe buffer size
+        bufsize = len(str)
+
+    pipe = Popen(cmd, True, bufsize)
+    if str:
+        pipe.tochild.write(str)
+        pipe.tochild.close()
+
+    out = ""
+    err = ""
+    while True:
+        str = pipe.fromchild.read()
+        if str:
+            out += str
+        code = pipe.poll()
+        if code > -1:
+            err = pipe.childerr.read()
+            break
+        if len(out) >= MAX:
+            err = "Output exceeds %s bytes and has been truncated"
+            break
+
+    return (code, out, err)