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

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Script doesn't read those "cvs server: Diffing" lines
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