command pipe concatenated messages

[Jim Mozley]

John P. Rouillard wrote:


> I would use ">> $pipe" to append data for two reasons:
> 
>   1 - > clobbers data already existing in files, not sure about in pipes
>   2 - atomic writes occur only if file is opened for append IIRC.
> 
> 
>>flock(PIPE, LOCK_EX);
> 
> 
> This should guarantee only one process is accessing the file, but I
> think you have already written to the file by using > in your open, so
> there may be a race condition.

IIRC it is not possible to open a filehandle to a pipe using ">> $pipe", 
one must use "> $pipe". I get "Cannot open pipe Illegal seek at ..." 
when trying.

Regards,

Jim


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