sleep
(PHP 4, PHP 5)
sleep — Delay execution
说明
int sleep ( int $seconds )Delays the program execution for the given number of seconds.
参数
- seconds
-
Halt time in seconds.
返回值
Returns zero on success, or FALSE on error.
If the call was interrupted by a signal, sleep() returns a non-zero value. On Windows, this value will always be 192 (the value of the WAIT_IO_COMPLETION constant within the Windows API). On other platforms, the return value will be the number of seconds left to sleep.
错误/异常
If the specified number of seconds is negative, this function will generate a E_WARNING.
更新日志
| 版本 | 说明 |
|---|---|
| 5.3.4 | Before PHP 5.3.4, on Windows, sleep() always returns NULL when sleep has occurred, regardless of whether the sleep was interrupted or not. |
范例
Example #1 sleep() example
This example will output (after 10 seconds)
<?php
// current time
echo date('h:i:s') . "
";
// sleep for 10 seconds
sleep(10);
// wake up !
echo date('h:i:s') . "
";
?>
05:31:23
05:31:33
参见
- usleep() - Delay execution in microseconds
- time_nanosleep() - Delay for a number of seconds and nanoseconds
- time_sleep_until() - Make the script sleep until the specified time
- set_time_limit() - 设置脚本最大执行时间
