how to catch error with system()

[eight02645999@yahoo.com]

hi

i have a piece of python code extract that calls an external java
program
cmd = """java someclass someargs"""
try:
ret = os.WEXITSTATUS( os.system(cmd))
except:
print blah
else:
dosomething(ret )

the thing is, the java class "someclass" produces it's own errors when
something goes wrong.
something like
java.io.FileNot FoundException: somefile (No such file or directory)
at java.io.FileInp utStream.open(N ative Method)
at java.io.FileInp utStream.<init> (FileInputStrea m.java:106)
at java.io.FileInp utStream.<init> (FileInputStrea m.java:66)
......

how can i supress this error from showing when i execute
../pythonscript.py and at the same time logging it to an errlog file??

thanks

[Diez B. Roggisch]

Re: how to catch error with system()

eight02645999@y ahoo.com wrote:
[color=blue]
> hi
>
> i have a piece of python code extract that calls an external java
> program
> cmd = """java someclass someargs"""
> try:
> ret = os.WEXITSTATUS( os.system(cmd))
> except:
> print blah
> else:
> dosomething(ret )
>
> the thing is, the java class "someclass" produces it's own errors when
> something goes wrong.
> something like
> java.io.FileNot FoundException: somefile (No such file or directory)
> at java.io.FileInp utStream.open(N ative Method)
> at java.io.FileInp utStream.<init> (FileInputStrea m.java:106)
> at java.io.FileInp utStream.<init> (FileInputStrea m.java:66)
> ......
>
> how can i supress this error from showing when i execute
> ./pythonscript.py and at the same time logging it to an errlog file??[/color]

You probably want to catche the subprocesses stdout/stderr streams. To do
so, use the subprocess module (if you are on python2.4), or the
popen2-module. See the docs for how to use them.

--
Regards,

Diez B. Roggisch