flock

After wrestling with PHP source for a half an hour, I gave up. :P The question is - what system call does the PHP flock() function call boil down to on a Gentoo Linux system? I'm having some issues with it (like block-for-30-seconds-in-every-one-of-20-loop-iterations kind of issues) and I would like to know why that is so. // example: $stream = fopen( FILE , 'rb') or die('???'); $md = stream_get_meta_data($stream); echo $md['wrapper_type']; flock($stream); if this prints plainfile then the call to the php function flock() is handled by php_stdiop_set_option(...) which calls flock(). Depending

im using a simple test script from http://www.tuxradar.com/practicalphp/8/11/0 like this <?php $fp = fopen("foo.txt", "w"); if (flock($fp, LOCK_EX)) { print "Got lock!\n"; sleep(10); flock($fp, LOCK_UN); } i opened 5 shell's and executed the script one after the other the scripts block until the lock is free'ed and then continues after released im not really interessted in php stuff, but my question is: anyone knows the order in which flock() is acquired? e.g. t0: process 1 lock's t1: process 2 try_lock < blocking t2: process 3 try_lock < blocking t3: process 1 releases lock t4: ?? which

Linux crontab 的配置存放 /var/spool/cron 目录下。 Linux crontab 的日志文件存放再 /var/log/cron* timeout 命令 timeout 给脚本加入超时时间控制 -s 发送信号 timeout 正常结束的返回码是 0 timeout 超时kill结束的返回码是 124 timeout -s 9 100 sleep 1000 flock命令 flock可以保证只有一个脚本单例执行。主要用的是互斥非阻塞模式 用于保证我们的脚本同时只能执行一次， -s 获取一个共享锁 -e 获取一个排它锁 -u 手动释放锁 -n 非阻塞模式 获取锁失败返回1 不是等待 -w 设置阻塞超时 -c 在shell中执行其后的语句 flock -xn /tmp/lock -c "/bin/sh /root/test.sh" 来源： https://www.cnblogs.com/tl542475736/p/11811607.html

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: Although the title mentions file, it doesn't have to be a file. Any locking mechanism would do. Here is the situation: I have a daemon process written in C, and a web page in php. I'd like to have a way of mutual locking so that under certain situation, the C daemon would lock a file and php detects the situation and tells the client side that the system is busy. Is there an easy way of doing this? Thanks, 回答1: flock does it properly. In your PHP script, use a non-blocking lock : $fd = fopen('/var/run/lock.file', 'r+'); if (!flock($fd, LOCK

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I'm mostly familiar with Java, C and C++ in which there are ways to control that only one thread is accessing a resource at any given time. Now I'm in search for something similar but in PHP 5.x. To formulate my problem with one example: I have an ASCII-file which only stores a number, the value of a page load counter. At application deployment the file will simply hold a 0. For each access the value will be incremented by one. The goal is to keep track of page loads. The problem comes when many users are concurrently accessing the page

How Should I Request a Non-Blocking Lock? Why doesn't Ruby's File#flock work as expected when separate attempts are made to lock a file? Locking the file in a block is not the correct solution for this issue because the point is to show the behavior of locking on persistent locks. Using File#flock inside a block releases the lock when the block exits, so it doesn't demonstrate the problem properly. File#flock fails in a variety of ways, especially when requesting a non-blocking lock. Some examples follow. Failing Examples with File#flock Infinite wait when using multiple exclusive locks, since

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: this my Flock code, why removeBoid not function public function Flock(){ ArrayList = new Array();// Initialize the arraylist } public function frun():void { for (var i:int = 0; i < ArrayList.length; i++){ ArrayList[i].brun(ArrayList);// Passing the entire list of boids to each boid individually}} public function addBoid(b:Boid):void{ ArrayList.push(b); addChild(b); } public function grun():void{ for (var i:int = 0; i < ArrayList.length; i--){ ArrayList[i].brun(ArrayList);// Passing the entire list of boids to each boid individually }} public

1.Cookie禁用了,Session还能用吗? 对应的服务器Session，Session ID是通过Cookie来传递的，禁用Cookie相当于失去了Session ID，就得不到Session a. s n = s e s s i o n i d ( ) ; s e s s i o n i d ( sn=session_id(); session_id( s n = s e s s i o n i d ( ) ; s e s s i o n i d ( b.fopen w+ 写入session_id() fread 取出sesson_id 2.GET、POST传输最大容量是多少？ GET发送http协议通过url方式传递，受浏览器或者服务器的设置限制 POST实体数据，表单传送，通过php.conf的post_max_size可以设置传输大小 3.抓取远程图片到本地，会用什么函数？ file_get_contents() file_put_contents() 4.CGI是什么？什么是FastCGI？php-fpm、FastCGI、Nginx之间是什么关系？ server收到一个php的请求时，会启动一个程序去处理当前的请求，而这个程序就是CGI 通用网关接口(返回标准html数据的服务) FastCGI 是一个协议，是应用程序和 WEB 服务器连接的桥梁。Nginx