[xmonad] Strange spawnPipe error

[Ferenc Wagner]

Viktor Deryagin <vderyagin at gmail.com> writes:

> On Sun, Dec 27, 2009 at 12:56 AM, Ferenc Wagner <wferi at niif.hu> wrote:
>
>> Very strange, all the setsid() syscalls are doubled like for example
>>
>> [pid 11584] setsid()                    = 11584
>> [pid 11584] setsid()                    = -1 EPERM (Operation not permitted)
>> [pid 11584] write(2, "xmonad-i386-linux: ", 19) = 19
>> [pid 11584] write(2, "createSession: permission denied"..., 58) = 58
>> [pid 11584] write(2, "\n", 1)           = 1
>
> Xmonad should run four instances of dzen2 (4 spawnPipe entries in
> xmonad.hs), maybe this is the reason?

There are four such pairs of setsid calls in your strace output,
corresponding to the four spawnPipes, but I don't understand why they
are *pairs*, like above...

> $ ghc --version
> The Glorious Glasgow Haskell Compilation System, version 6.10.4

Same as mine.

>> What is your unix package version?
>
> What is "unix package"? Sorry for stupid question :)

Here's the way to find out:
$ ghc-pkg describe unix | grep version
version: 2.3.2.0

>> Please compile the following test program, run it under strace -f and
>> send the output back:
>
> Attached.

Thanks, this contains a simple setsid() call, as it should.  Please test
another short program the same way:

> import XMonad.Util.Run
> main = spawnPipe "cat"
-- 
Thanks,
Feri.