[Qt-interest] Problems running QProcess under linux

[Bill Crocker]

Scott Aron Bloom wrote:
> No reading from the console, only writing.
>

Since we are fishing...

The QProcess child context will have less swap space available
since there is at least one more process running... the parent.

> Scott
> 
> -----Original Message-----
> From: qt-interest-bounces+scott.bloom=onshorecs.com at qt.nokia.com
> [mailto:qt-interest-bounces+scott.bloom=onshorecs.com at qt.nokia.com] On
> Behalf Of Thiago Macieira
> Sent: Monday, September 26, 2011 11:04 AM
> To: qt-interest at qt.nokia.com
> Subject: Re: [Qt-interest] Problems running QProcess under linux
> 
> On Monday, 26 de September de 2011 13:37:19 Bill Crocker wrote:
>> Scott Aron Bloom wrote:
>>> Thanks.. the problem here is the crash takes 3-4 hours of running to
> 
>>> crash..  and has yet to be reproduced when run with the same command
> 
>>> line arguments from the CLI only...  hence my thoughts that it might
> 
>>> be a QProcess settings issue...
>> Create a small program which dumps all resource limits using 
>> getrlimit. Run this from a QProcess and see if the limits differ from 
>> a command line run.
>>
>> You can also dump its list of env vars and see if there are any 
>> differences there.
> 
> Usually, the only difference between running from the command line and
> using QProcess is stdin, stdout and stderr. From the command-line, they
> are connected to a terminal; from QProcess, they are connected to a
> pipe.
> 
> By default, libc uses line-buffering with stdout when connected to a
> terminal, but full buffering when it's a file or pipe,
> 
> Also, reading from a terminal respects terminal settings (canonical
> mode, for example), whereas reading from a file or pipe is just that:
> reading.
> 
> It might be that the child process attempts to read a chunk of data
> expecting to get at most one line, but it eventually gets more than that
> and then falls out of sync.
> 
> --
> Thiago Macieira - thiago (AT) macieira.info - thiago (AT) kde.org
>    Software Architect - Intel Open Source Technology Center
>       PGP/GPG: 0x6EF45358; fingerprint:
>       E067 918B B660 DBD1 105C  966C 33F5 F005 6EF4 5358
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