stream_select
stream_set_blocking does not unblock streams opened with popen. (tested in php 5.1.6)
stream_set_blocking
(PHP 4 >= 4.3.0, PHP 5)
stream_set_blocking — Configure le mode bloquant d'un flux
Description
bool stream_set_blocking
( resource $stream
, int $mode
)
stream_set_blocking() configure le mode bloquant du flux stream . Si mode vaut 0, stream sera configuré en mode non-bloquant, et s'il vaut 1, stream sera configuré en mode bloquant. Cet appel affecte les fonctions telles que fgets() et fread() qui lisent dans des flux. En mode non-bloquant, la fonction fgets() s'exécute juste après son appel, alors qu'en mode bloquant, elle attendra des données.
Cette fonction retourne TRUE en cas de succès, FALSE en cas d'échec.
stream_set_blocking() était appelée set_socket_blocking() et plus tard socket_set_blocking() mais ces appellations sont obsolètes.
Note: Avant PHP 4.3, cette fonction ne fonctionnait que sur les flux utilisant des sockets. Depuis PHP 4.3, cette fonction peut fonctionner avec n'importe quel flux qui supporte le mode non-bloquant (actuellement, les fichiers réguliers et les flux de sockets).
Voir aussi stream_select().
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User Contributed Notesstream_set_blocking
arjuna
06-Aug-2008 12:31
06-Aug-2008 12:31
22-Mar-2007 09:33
A concise description of Blocking vs. Non-blocking:
http://tinyurl.com/ype2j7
http://www.franz.com/support/documentation/7.0/ doc/streams.htm#block-non-block-3
5.2.1 Blocking behavior in simple-streams
There are three modes of blocking behavior when writing
items in a sequence to a stream or filling a sequence with items read from a stream. The issue is what to do when (for writing) the entire sequence cannot be written and (for reading) the entire sequence cannot be filled, but no EOF is encountered. (By `the entire sequence', we mean that part specified by start and end if those are supplied.) Here are the modes and a description of what happens in that mode if the whole operation does not complete and no EOF is encountered.
1. Blocking mode: the system blocks (waits or hangs) until the operation can be completed.
2. Blocking/Non-Blocking (B/NB) mode: the system only blocks on the first element of the sequence: if it cannot be written or read, the system blocks. If the first element is successfully written or read, and a subsequent element cannot be written or read, the function doing the writing/reading returns, typically with the return value(s) indicating exactly what was accomplished.
3. Non-Blocking mode: the system never blocks. If an element cannot be written or read, the function doing the writing/reading returns, typically with the return value(s) indicating exactly what was accomplished.
galvao at galvao dot eti dot br
15-Dec-2006 05:58
15-Dec-2006 05:58
Please notice that this function will not work as for PHP 5.2.0 at least on Win32 systems. It probably won't work on Linux boxes either.
PHP just ignores the function and blocking remains active.
For more information take a look at Bug #36918.
MagicalTux at ookoo dot org
08-Sep-2006 08:13
08-Sep-2006 08:13
When you use fwrite() on a non-blocking stream, data isn't discarded silently as t dot starling said.
Remember that fwrite() returns an int, and this int represents the amount of data really written to the stream. So, if you see that fwrite() returns less than the amount of written data, it means you'll have to call fwrite() again in the future to write the remaining amount of data.
You can use stream_select() to wait for the stream to be available for writing, then continue writing data to the stream.
Non-blocking streams are useful as you can have more than one non-blocking stream, and wait for them to be available for writing.
t dot starling at physics dot unimelb dot edu dot au
08-Sep-2005 01:02
08-Sep-2005 01:02
Warning: if you write too much data to a stream in non-blocking mode and fill the buffer, the excess will be silently discarded. Observed in PHP 4.4.0 under linux.