[darcs-devel] rollback.sh

[Thorkil Naur]

Hello,

On Sunday 09 March 2008 01:01, zooko wrote:
> If I run this bash command line on Mac OS 10.4:
> 
> $ perl shell_harness rollback.sh
> 
> Then it runs the rollback.sh test and quickly finishes successfully.
> 
> If I run this command-line:
> 
> $ python -c 'import os;os.system("perl shell_harness rollback.sh")'
> 
> Which does approximately the same thing, then it hangs indefinitely.
> 
> There's something else curious about it -- twice during my  
> experimentation I interrupted a test to the bash prompt back, but the  
> test left several processes running in the background: bash, and yes,  
> but not darcs or perl.

On a PPC Mac OS X 10.4, I have experienced something that could be similar: As 
I recall, it was a pipe like

> yes abc | head -n 1000 | ... (something more)

for generating some large number of bytes as input to a test program. When run 
from the command line, it worked fine. When executed from a shell, it never 
returned, leaving a yes process (and perhaps others) that seemingly just used 
CPU but never stopped.

On Sunday 09 March 2008 01:17, Mark Stosberg wrote:
> ...
> Very interesting. What if you apply the patch I sent to darcs-devel
> recently? It just replaces the use of "yes | darcs rollback" with 
> "darcs rollback -a"

This could very well be worth trying, whatever it is, because it eliminates 
the use of yes.

> ...

Best regards
Thorkil