| Type: | integer |
| Default: | 0 (0ms) |
| Min: | 0 (0ms) |
| Max: | 2147483647 (2147483647ms) |
| Unit: | milliseconds (ms) |
| Context: | user |
| Restart: | false |
| Since: | 12 |
Specifies the amount of time that transmitted data may remain unacknowledged before the TCP connection is forcibly closed. If this value is specified without units, it is taken as milliseconds. A value of 0 (the default) selects the operating system's default. This parameter is supported only on systems that support TCP_USER_TIMEOUT (which does not include Windows); on other systems, it must be zero. In sessions connected via a Unix-domain socket, this parameter is ignored and always reads as zero.