Windows中的PHP CLI:处理Ctrl-C命令

以下内容适用于unix系统。

我们可以使用stream_get_contents（）捕获键，但它不能捕获CTRL键。此外，过滤^C也不起作用。

我们需要做的是捕捉SIGINT posix信号。

按CTRL+c默认行为

程序不会退出，您需要实现另一种退出方式！：

function shutdown(){};
pcntl_signal(SIGINT,"shutdown");

要处理CTRL+c，并在退出前运行一些代码：

function shutdown(){
    echo "'033c";                                        // Clear terminal
    system("tput cnorm && tput cup 0 0 && stty echo");   // Restore cursor default
    echo PHP_EOL;                                        // New line
    exit;                                                // Clean quit 
}
register_shutdown_function("shutdown");                  // Handle END of script
declare(ticks = 1);                                      // Allow posix signal handling
pcntl_signal(SIGINT,"shutdown");                         // Catch SIGINT, run shutdown()                    

---

POSIX信号列表：

Php抓不到SIGKILL，不可能。

SIGABRT and SIGIOT
    The SIGABRT and SIGIOT signal is sent to a process to tell it to abort, i.e. to terminate. The signal is usually initiated by the process itself when it calls abort() function of the C Standard Library, but it can be sent to the process from outside like any other signal.
SIGALRM, SIGVTALRM and SIGPROF
    The SIGALRM, SIGVTALRM and SIGPROF signal is sent to a process when the time limit specified in a call to a preceding alarm setting function (such as setitimer) elapses. SIGALRM is sent when real or clock time elapses. SIGVTALRM is sent when CPU time used by the process elapses. SIGPROF is sent when CPU time used by the process and by the system on behalf of the process elapses.
SIGBUS
    The SIGBUS signal is sent to a process when it causes a bus error. The conditions that lead to the signal being sent are, for example, incorrect memory access alignment or non-existent physical address.
SIGCHLD
    The SIGCHLD signal is sent to a process when a child process terminates, is interrupted, or resumes after being interrupted. One common usage of the signal is to instruct the operating system to clean up the resources used by a child process after its termination without an explicit call to the wait system call.
SIGCONT
    The SIGCONT signal instructs the operating system to continue (restart) a process previously paused by the SIGSTOP or SIGTSTP signal. One important use of this signal is in job control in the Unix shell.
SIGFPE
    The SIGFPE signal is sent to a process when it executes an erroneous arithmetic operation, such as division by zero. This may include integer division by zero, and integer overflow in the result of a divide (only INT_MIN/-1, INT64_MIN/-1 and %-1 accessible from C).[2][3].
SIGHUP
    The SIGHUP signal is sent to a process when its controlling terminal is closed. It was originally designed to notify the process of a serial line drop (a hangup). In modern systems, this signal usually means that the controlling pseudo or virtual terminal has been closed.[4] Many daemons will reload their configuration files and reopen their logfiles instead of exiting when receiving this signal.[5] nohup is a command to make a command ignore the signal.
SIGILL
    The SIGILL signal is sent to a process when it attempts to execute an illegal, malformed, unknown, or privileged instruction.
SIGINT
    The SIGINT signal is sent to a process by its controlling terminal when a user wishes to interrupt the process. This is typically initiated by pressing Ctrl+C, but on some systems, the "delete" character or "break" key can be used.[6]
SIGKILL
    The SIGKILL signal is sent to a process to cause it to terminate immediately (kill). In contrast to SIGTERM and SIGINT, this signal cannot be caught or ignored, and the receiving process cannot perform any clean-up upon receiving this signal. The following exceptions apply:
        Zombie processes cannot be killed since they are already dead and waiting for their parent processes to reap them.
        Processes that are in the blocked state will not die until they wake up again.
        The init process is special: It does not get signals that it does not want to handle, and thus it can ignore SIGKILL.[7] An exception from this exception is while init is ptraced on Linux.[8][9]
        An uninterruptibly sleeping process may not terminate (and free its resources) even when sent SIGKILL. This is one of the few cases in which a UNIX system may have to be rebooted to solve a temporary software problem.
    SIGKILL is used as a last resort when terminating processes in most system shutdown procedures if it does not voluntarily exit in response to SIGTERM. To speed the computer shutdown procedure, Mac OS X 10.6, aka Snow Leopard, will send SIGKILL to applications that have marked themselves "clean" resulting in faster shutdown times with, presumably, no ill effects.[10] The command killall -9 has a similar, while dangerous effect, when executed e.g. in Linux; it doesn't let programs save unsaved data. It has other options, and with none, uses the safer SIGTERM signal.
SIGPIPE
    The SIGPIPE signal is sent to a process when it attempts to write to a pipe without a process connected to the other end.
SIGPOLL
    The SIGPOLL signal is sent when an event occurred on an explicitly watched file descriptor.[11] Using it effectively leads to making asynchronous I/O requests since the kernel will poll the descriptor in place of the caller. It provides an alternative to active polling.
SIGRTMIN to SIGRTMAX
    The SIGRTMIN to SIGRTMAX signals are intended to be used for user-defined purposes. They are real-time signals.
SIGQUIT
    The SIGQUIT signal is sent to a process by its controlling terminal when the user requests that the process quit and perform a core dump.
SIGSEGV
    The SIGSEGV signal is sent to a process when it makes an invalid virtual memory reference, or segmentation fault, i.e. when it performs a segmentation violation.[12]
SIGSTOP
    The SIGSTOP signal instructs the operating system to stop a process for later resumption.
SIGSYS
    The SIGSYS signal is sent to a process when it passes a bad argument to a system call. In practice, this kind of signal is rarely encountered since applications rely on libraries (e.g. libc) to make the call for them. SIGSYS can be received by applications violating the Linux Seccomp security rules configured to restrict them.
SIGTERM
    The SIGTERM signal is sent to a process to request its termination. Unlike the SIGKILL signal, it can be caught and interpreted or ignored by the process. This allows the process to perform nice termination releasing resources and saving state if appropriate. SIGINT is nearly identical to SIGTERM.
SIGTSTP
    The SIGTSTP signal is sent to a process by its controlling terminal to request it to stop (terminal stop). It is commonly initiated by the user pressing Ctrl+Z. Unlike SIGSTOP, the process can register a signal handler for, or ignore, the signal.
SIGTTIN and SIGTTOU
    The SIGTTIN and SIGTTOU signals are sent to a process when it attempts to read in or write out respectively from the tty while in the background. Typically, these signals are received only by processes under job control; daemons do not have controlling terminals and, therefore, should never receive these signals.
SIGTRAP
    The SIGTRAP signal is sent to a process when an exception (or trap) occurs: a condition that a debugger has requested to be informed of – for example, when a particular function is executed, or when a particular variable changes value.
SIGURG
    The SIGURG signal is sent to a process when a socket has urgent or out-of-band data available to read.
SIGUSR1 and SIGUSR2
    The SIGUSR1 and SIGUSR2 signals are sent to a process to indicate user-defined conditions.
SIGXCPU
    The SIGXCPU signal is sent to a process when it has used up the CPU for a duration that exceeds a certain predetermined user-settable value.[13] The arrival of a SIGXCPU signal provides the receiving process a chance to quickly save any intermediate results and to exit gracefully, before it is terminated by the operating system using the SIGKILL signal.
SIGXFSZ
    The SIGXFSZ signal is sent to a process when it grows a file that exceeds the maximum allowed size.
SIGWINCH
    The SIGWINCH signal is sent to a process when its controlling terminal changes its size (a window change).[14]

从PHP 7.4开始，现在可以通过向sapi_windows_set_ctrl_handler()函数注册处理程序回调来实现这一点。

sapi_windows_generate_ctrl_event()补充了这一点，它可以用于将信号调度到与调用方连接到同一控制台的其他进程。

只有CTRL-C和CTRL-BREAK事件可以在用户空间中处理，关闭/注销/关闭事件无法安全执行，因为在调用处理程序函数时，操作系统可能处于不可预测的部分关闭状态，因此此时执行的任何代码都有弊大于利的风险。

您可以在MSDN上找到有关底层机制的更多信息：

• SetConsoleCtrlHandler()
• GenerateConsoleCtrlEvent()

PHP API几乎与底层的C API相同，唯一显著的区别是PHP只允许注册一个回调，因此处理程序没有有意义的返回值，引擎只是将事件标记为已处理。这是为了保持实现的简单性，因为一堆函数可以很容易地在userland中实现，同样，如果您不想处理事件，可以简单地调用exit。

如果你想通过命令行在PHP中运行一个耗时很长的任务，我会尝试将其组织在徽章中，并跟踪已经完成的任务。

现在，您可以完全处理每个徽章（例如：处理并将其存储在xml文件中），而不仅仅是在处理完整个列表之后。因此，在两者之间发生碰撞/停车只会取消一个徽章，而不是所有徽章。

如果您将当前职位存储在每个徽章之后的某个位置，则可以在脚本崩溃或停止时轻松恢复。

现在，如果您检查操作系统进程列表以查看脚本是否正在运行，则可以编写一个cron作业，如果脚本崩溃且尚未运行，则该作业每X分钟启动一次脚本。

所以，TL；博士

• 处理小徽章中的作业
• 上次成功处理徽章的存储位置
• 在启动时检查是否已运行进程
• 不断地启动脚本，直到所有人都满意为止

除此之外，我喜欢PHP用于小型命令行作业，但如果您有这么大的任务，其他任务可能更适合。检查是否有可以长期稳定运行的东西，并有显示其进展的方法。也许是一个带有极简主义gui的小型C#应用程序。