Problem s FIFO (mirne OT)

[Stanislav Meduna]

On 9 Jun 1999 14:39:37 +0200, Petr Novotny wrote:

: Moment, neni nekde (POSIX?) zaruceno, za zapisy write() do roury 
: po nejakou velikost jsou atomicke? Dokonce jsem si i myslel, ze 
: by to mohlo byt 512 bytu. Netusim, kde jsem to cetl :-(

The single Unix specification, Version 2 skutocne pise:

Write requests to a pipe or FIFO will be handled the same
as a regular file with the following exceptions: 
...
Write requests of {PIPE_BUF} bytes or less will not be
interleaved with data from other processes doing writes
on the same pipe. Writes of greater than {PIPE_BUF}
bytes may have data interleaved, on arbitrary boundaries,
with writes by other processes, whether or not the
O_NONBLOCK flag of the file status flags is set. 


PIPE_BUF na Linuxe je 4096, POSIX garantuje
aspon 512 byte.

Zdravi
-- 
				Stano