Bug #74479 [Com]: usleep with large numbers
Edit report at https://bugs.php.net/bug.php?id=74479&edit=1
ID: 74479
Comment by: daverandom@php.net
Reported by: korchasa at gmail dot com
Summary: usleep with large numbers
Status: Open
Type: Bug
Package: Unknown/Other Function
Operating System: Ubuntu 16.04.2 with 4.8.0-46
PHP Version: 5.6.30
Block user comment: N
Private report: N
New Comment:
This is a 32-bit integer overflow issue, it will happen regardless of platform because there is an
explicit (unsigned int) cast when the underlying usleep(3) is called. https://lxr.room11.org/xref/php-src%40master/ext/standard/basic_functions.c#4520
I would argue that you shouldn't use usleep() to sleep for that kind of time anyway - if you
are sleeping for 12 hours, sub-second precision doesn't really matter and is not reasonable to
expect.
However in 64-bit environments the expected behaviour could be emulated.
Previous Comments:
------------------------------------------------------------------------
[2017-04-20 14:32:05] korchasa at gmail dot com
Description:
------------
usleep works strange on large numbers
Test script:
---------------
<?php
$start = microtime(true);
usleep(4294967296 + 1000000);
echo round(microtime(true) - $start);
Expected result:
----------------
12h pause and 4296 in output or error message
Actual result:
--------------
1 second pause and 1 in output
------------------------------------------------------------------------
--
Edit this bug report at https://bugs.php.net/bug.php?id=74479&edit=1
Thread (3 messages)