Command /bin/sh emitted errors - ios

Question

In xcode it is a good idea to generate documentation during build your library.. I am using headerdoc2HTML command .. to make it run with build phase I've added it to build phase script (shell script) like this:
headerdoc2html -o "outputPath" "myHeader.h"
But it always gives me an error:
Command /bin/sh emitted errors but did not return a nonzero exit code to indicate failure
Even the documentation is generated but it gives me an error .. if I remove this command every thing goes fine!
I checked with -d parameter I did not get where is the error
Any help with that? is there a way to check if the command did not return 0 then don't show error (ignore all warnings and errors)?
EDIT:
I just made sure that the command is ok and no problem with it by doing this check:
if headerdoc2html -q -j -o "outputPath" "myHeader.h"
then
echo "Documents generated successfully!"
fi

Answer 1

While the problem is from the command it self and don't effect the over all build phase so it is good idea to not show the warnings and errors from headerdoc2html command.
The easiest way to do that is to hide any emitted errors from it like by redirect errors to null like this:
headerdoc2html -o "outputPath" "myHeader.h" >/dev/null 2>/dev/null