PHP 7.1.0 Release Candidate 4 Released


(PHP 4 >= 4.2.0, PHP 5)

socket_set_blockSets blocking mode on a socket resource


bool socket_set_block ( resource $socket )

The socket_set_block() function removes the O_NONBLOCK flag on the socket specified by the socket parameter.

When an operation (e.g. receive, send, connect, accept, ...) is performed on a blocking socket, the script will pause its execution until it receives a signal or it can perform the operation.



A valid socket resource created with socket_create() or socket_accept().

Return Values

Returns TRUE on success or FALSE on failure.


Example #1 socket_set_block() example



This example creates a listening socket on all interfaces on port 1223 and sets the socket to O_BLOCK mode. socket_accept() will hang until there is a connection to accept.

See Also

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User Contributed Notes 1 note

laacz at laacz dot lv
1 year ago
Besides true and false socket_set_block might return NULL if you're not too careful. That would happen when passing non socket resource as first parameter.

E.g. socket_set_block(false)) would return NULL and emit warning that you're trying to do things with non-socket.
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