[Tutor] stderr

[Corran Webster]

On 13 Apr, Arne Mueller wrote:
> Hi All,
> 
> is there an easy way like in C or perl to use 'print' to write to stderr
> instead stdout?
> 
> python> print sys.stderr 'error' 
> 
> that doesn't work :-(
> 
> assigning sys.stdout to sys.stderr is not a good solution. I dont want
> to reassign stderr/stdout everytime I switch between error messages and
> data output.
> 
> python> sys.stdout = sys.stderr
> python> print 'error'
> 
> ... work but is not usefull

sys.stderr is a file object, so

sys.stderr.write("Oops!\n")

is equivalent to printing "Oops" to stderr after switching.  If you
need to vary the contents of the message, you'll probably find the %
string formatting commands useful:

sys.stderr.write("Oops!  Error: %d, %s\n" % (errnum, message))

Regards,
Corran