Getting output from executed command that is not STDIN

[Sami Viitanen]

Hello,

I'm using os.popen and read for reading command input to string but the
string doesn't contain the same output that running the command manually or
with os.system contains.

with os.system:
cvs server: Diffing //Project1
File //Project1/testiware.txt is new; current revision 3.13
File //Project1/what_is_version_control.txt is new; current revision 3.3
cvs server: Diffing //Project1/Dir1
File //Project1/Dir1/seltest.c is new; current revision 1.4
File //Project1/Dir1/testi.c is new; current revision 1.2

with os.popen and read:
File //Project1/testiware.txt is new; current revision 3.13
File //Project1/what_is_version_control.txt is new; current revision 3.3
File //Project1/Dir1/seltest.c is new; current revision 1.4
File //Project1/Dir1/testi.c is new; current revision 1.2

 

[Fredrik Lundh]

I'm using os.popen and read for reading command input to string but the
string doesn't contain the same output that running the command manually or
with os.system contains.

with os.system:
cvs server: Diffing //Project1
File //Project1/testiware.txt is new; current revision 3.13
File //Project1/what_is_version_control.txt is new; current revision 3.3
cvs server: Diffing //Project1/Dir1
File //Project1/Dir1/seltest.c is new; current revision 1.4
File //Project1/Dir1/testi.c is new; current revision 1.2

with os.popen and read:
File //Project1/testiware.txt is new; current revision 3.13
File //Project1/what_is_version_control.txt is new; current revision 3.3
File //Project1/Dir1/seltest.c is new; current revision 1.4
File //Project1/Dir1/testi.c is new; current revision 1.2

looks like the program prints some output to stderr, and some to stdout.
possible solutions:

1) if your shell supports it, add "2>&1" to the end of the command line,
to send all stderr output to stdout. random google link:
http://www.zeitfenster.de/bash/Bash-Prog-Intro-HOWTO-3.html

2) use os.popen4 to get a file handle representing both streams. see:
http://www.python.org/doc/current/lib/os-newstreams.html#os-newstreams

</F>

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