'cmd /C start cmd' no longer non-blocking (base-cygwin 3.1-1), but used to work (in base-cygwin 3.0-1)

Andrey Repin anrdaemon@freemail.ru
Sat May 5 11:35:00 GMT 2012

Greetings, Petrisor Eddy-Marian-B36037!

> I am using at work cygwin on various machines (XP and Windows 7) and made
> several scripts that use gnu utilities from cygwin. One of those is a script
> that starts in paralel instances of cmd various parts of a build system
> through a sh script that invokes 'cmd /C start ...'

Why? Aren't your default ComSpec isn't CMD already?

> to start those parts of the build system in a non-blocking fashion.

If it's (b?a|tc)?sh script - use backgrounding (The &)
If it's a CMD script - use backgrounding (START "" /B "command" args)
Problem solved.

> Recently, on one of the machines which had its cygwin installation upgraded,
> I have observed that the cmd instances do not start in a non-blocking
> fashion anymore, but instead wait for the process to finish.

> To be more precise, following the following steps should lead to two
> interactive windows, one with the sh prompt and one with the cmd prompt,
> both waiting for user input:
> 1 - start a cygwin (or sh) command window
> 2 - type "cmd /C start cmd"

> Expected result:
> Two interactive and usable windows, one with the sh prompt, one with the cmd
> prompt, both waiting for user input.

For new interactive windows from withing Cygwin shell - use run program. And
again, backgrounding, if necessary.

> Actual result:
> Two windows, one with sh and one with cmd, Cygwin/sh window blocked and waiting for the cmd window to finish.

Andrey Repin (anrdaemon@freemail.ru) 05.05.2012, <15:27>

Sorry for my terrible english...

Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple

More information about the Cygwin mailing list