(PHP 4 >= 4.1.0, PHP 5, PHP 7, PHP 8)
socket_write — Write to a socket
socket_write(Socket $socket, string $data, ?int $length = null): int|false
The function socket_write() writes to the socket from the given data.
socketdataThe buffer to be written.
length The optional parameter length can specify an alternate length of bytes written to the socket. If this length is greater than data's length, it is silently truncated to the length of data.
Returns the number of bytes successfully written to the socket or false on failure. The error code can be retrieved with socket_last_error(). This code may be passed to socket_strerror() to get a textual explanation of the error.
Note:
It is perfectly valid for socket_write() to return zero which means no bytes have been written. Be sure to use the
===operator to check forfalsein case of an error.
| Version | Description |
|---|---|
| 8.0.0 | socket is a Socket instance now; previously, it was a resource. |
| 8.0.0 | length is nullable now. |
Note:
socket_write() does not necessarily write all bytes from
data. It's valid that, depending on the network buffers etc., only a certain amount of data, even one byte, is written despitedatabeing longer. A loop must be used to ensure that the rest ofdatais transmitted.
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https://www.php.net/manual/en/function.socket-write.php