Hello,
I''m trying to write a utility to run an external process and capture
it''s stderr. It seems that IO.popen only lets me read the stdout. Any
tips for how to read stderr?
Mike
snippet of code...
def process_file(filename)
@filename = filename
puts "Processing: " + @filename
cmdline = "ffmpeg -i " + @filename
ffmpeg = IO.popen(cmdline, "w+")
ffmpeg.close_write
result = ffmpeg.gets
result.each do |line|
puts "Line from ffmpeg: " + line
end
end
This code does not work because the good stuff I want from ffmpeg went
to stderr and not stdout. Please refrain from commenting on the merits
of ffmpeg. That could go on all day. :-)
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Hello again,
No takers so far...
I tried this:
IO.popen(cmdline, "w+") { |f| puts f.gets }
and the command executes but my silly command (fffmpeg) writes all the
good stuff to stderr. I grep''ed the source for ffmpeg and there are :
$ grep -r fprintf.stderr * | wc
284 2271 25075
way to many for me to want to change. Is there some cool command line
trick to map stderr to stdout?
Thanks for any help...
Mike
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This has probably long-been resolved for you, but for others who end up here hoping for the answer.. You can just stick "2>&1" in the argument to IO.popen after your command, like so: ffmpeg = IO.popen(cmdline + " 2>&1", "w+") -- Posted via http://www.ruby-forum.com/. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk-unsubscribe-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---