classification
Title: Popen3 might cause dead lock
Type: enhancement Stage:
Components: Documentation Versions:
process
Status: closed Resolution: fixed
Dependencies: Superseder:
Assigned To: fdrake Nosy List: fdrake, guettli
Priority: normal Keywords:

Created on 2002-03-16 09:49 by guettli, last changed 2002-06-18 20:41 by guettli. This issue is now closed.

Messages (3)
msg9740 - (view) Author: Thomas Guettler (guettli) Date: 2002-03-16 09:49
Please include a hint in the documentation of popen3
that it can produce a dead lock.

Example:

The subprocess writes a lot of data to stderr and
blocks and your application reads from stdout. It
might result in a dead lock

An other explanation to this can be found here:
http://mail.python.org/pipermail/python-dev/2000-September/009460.html

Unfortunately popen3 is documented twice. Would be nice
if there is a
hint to deadlocks at both places. I am programming
quite long and I
lost hours debugging why this happens sometimes and
sometimes not. (It
only happens if you have a lot of output)

In the documentation of Perl there is a hint
to this problem, too.

thomas

(I already submitted this feature request to
python-docs@python.org. But received no response)







msg9741 - (view) Author: Fred L. Drake, Jr. (fdrake) (Python committer) Date: 2002-06-18 20:32
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Added a section on flow control issues to the documentation
for the popen2 module, with a reference from the
corresponding functions in the os module.

Doc/lib/libos.tex:     1.90, 1.74.2.1.2.5, 1.53.4.9.
Doc/lib/libpopen2.tex: 1.16, 1.15.12.1, 1.13.6.2.
msg9742 - (view) Author: Thomas Guettler (guettli) Date: 2002-06-18 20:41
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user_id=22123

Thank you very much!
History
Date User Action Args
2002-03-16 09:49:28guettlicreate