PHP: 交互式 shell

交互式 shell

如果 PHP 使用 --with-readline 选项编译，则 CLI SAPI 使用 -a 选项时会提供交互式 shell。自 PHP 7.1.0 起，如果启用了 readline 扩展，交互式 shell 也可以在 Windows 上使用。

使用交互式 shell，你可以输入 PHP 代码并直接执行。

示例 #1 使用交互式 shell 执行代码

$ php -a
Interactive shell

php > echo 5+8;
13
php > function addTwo($n)
php > {
php { return $n + 2;
php { }
php > var_dump(addtwo(2));
int(4)
php >

交互式 shell 还有对函数、常量、类名、变量、静态方法调用和类常量的 Tab 键补全功能。

示例 #2 Tab 键补全

当可能有多个补全时，按两次 Tab 键将会得到补全列表：

php > strp[TAB][TAB]
strpbrk   strpos    strptime  
php > strp

当仅可能有一个补全，按一次 Tab 键即可在同一行中补全剩余：

php > strpt[TAB]ime(

补全也适用于当前交互式 shell 会话期间定义的名称：

php > $fooThisIsAReallyLongVariableName = 42;
php > $foo[TAB]ThisIsAReallyLongVariableName

交互式 shell 会存储你的操作历史记录，可以通过上下键访问。历史记录存储于 ~/.php_history 文件。

CLI SAPI 提供了 cli.pager 和 cli.prompt 两个 php.ini 配置。cli.pager 配置允许外部程序（例如 less）充当分页器输出而不是直接在屏幕上显示。 cli.prompt 配置可以更改 php > 提示符。

在交互式 shell 中还可以使用缩写符号设置 php.ini 配置。

示例 #3 在交互式 shell 中设置 php.ini 配置

cli.prompt 配置：

php > #cli.prompt=hello world :> 
hello world :>

使用反引号可以在提示中执行 PHP 代码：

php > #cli.prompt=`echo date('H:i:s');` php > 
15:49:35 php > echo 'hi';
hi
15:49:43 php > sleep(2);
15:49:45 php >

设置分页器为 less：

php > #cli.pager=less
php > phpinfo();
(output displayed in less)
php >

cli.prompt 配置支持一些转义字符：

**`cli.prompt` 转义字符**
字符	描述
`\e`	用于添加提示符颜色。一个例子是 `\e[032m\v \e[031m\b \e[34m\> \e[0m`
`\v`	PHP 版本。
`\b`	指明 PHP 所在的块。例如 `/*` 表示在多行注释中。外部作用域用 `php` 来表示。
`\>`	指明提示字符。默认是 `>`，但当 shell 位于未结束的块或者字符串时会发生变化。可能的字符有 `' " { ( >`

注意:
在该模式下，通过 auto_prepend_file 和 auto_append_file 解析加载的文件会有一些限制 —— 例如函数必须在调用前定义。

交互模式

如果 readline 扩展不可用，在 PHP 8.1.0 之前，使用 -a 选项调用 CLI SAPI 会提供交互模式。在此模式中，一个完整的 PHP 脚本应该通过 STDIN 给出，并用 CRTL+d （POSIX）或者 CTRL+z 终止然后 ENTER （Windows），脚本执行。这与不加 -a 选项调用 CLI SAPI 基本相同。

自 PHP 8.1.0 起，如果 readline 扩展不可用，使用 -a 调用 CLI SAPI 会失败。

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用户贡献的备注 7 notes

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177

Ryan P ¶

12 years ago

Interactive Shell and Interactive Mode are not the same thing, despite the similar names and functionality.

If you type 'php -a' and get a response of 'Interactive Shell' followed by a 'php>' prompt, you have interactive shell available (PHP was compiled with readline support). If instead you get a response of 'Interactive mode enabled', you DO NOT have interactive shell available and this article does not apply to you.

You can also check 'php -m' and see if readline is listed in the output - if not, you don't have interactive shell.

Interactive mode is essentially like running php with stdin as the file input. You just type code, and when you're done (Ctrl-D), php executes whatever you typed as if it were a normal PHP (PHTML) file - hence you start in interactive mode with '<?php' in order to execute code.

Interactive shell evaluates every expression as you complete it (with ; or }), reports errors without terminating execution, and supports standard shell functionality via readline (history, tab completion, etc). It's an enhanced version of interactive mode that is ONLY available if you have the required libraries, and is an actual PHP shell that interprets everything you type as PHP code - using '<?php' will cause a parse error.

Finally, if you're running on Windows, you're probably screwed. From what I'm seeing in other comments here, you don't have readline, and without readline there is no interactive shell.

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spencer at aninternetpresence dot net ¶

13 years ago

In Windows, press Enter after your ending PHP tag and then hit Ctrl-Z to denote the end-of-file:



C:\>php -a

Interactive mode enabled



<?php

echo "Hello, world!";

?>

^Z

Hello, world!



You can use the up and down arrows in interactive mode to recall previous code you ran.

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#linuxmint-es ¶

7 years ago

For use interactive mode enabled on GNU/Linux on distros Debian/Ubuntu/LinuxMint you must install "php*-cli" and "php*-readline" packages from official repository.
Example:
 >$sudo aptitude install php5-cli php5-readline

After that you can use interactive mode.
Example:
~ $ php -a
Interactive mode enabled

php >echo "hola mundo!\n";
hola mundo!
php >

I hope somebody help it!

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Anonymous ¶

14 years ago

Just a few more notes to add...

1) Hitting return does literally mean "execute this command".  Semicolon to note end of line is still required.  Meaning, doing the following will produce a parse error:

php > print "test"
php > print "asdf";

Whereas doing the following is just fine:

php > print "test"
php > ."asdf";

2) Fatal errors may eject you from the shell:

name@local:~$ php -a
php > asdf();

Fatal Error: call to undefined function...
name@local:~$

3) User defined functions are not saved in history from shell session to shell session.

4) Should be obvious, but to quit the shell, just type "quit" at the php prompt.

5) In a sense, the shell interaction can be thought of as linearly following a regular php file, except it's live and dynamic.  If you define a function that you've already defined earlier in your current shell, you will receive a fatal "function already defined" error only upon entering that closing bracket.  And, although "including" a toolset of custom functions or a couple of script addon php files is rather handy, should you edit those files and wish to "reinclude" it again, you'll cause a fatal "function x already defined" error.

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John ¶

6 years ago

If you delete your "~/.php_history", you MUST re-create the file manually!

Because after I deleted my history file, "php -a" (interactive mode) never saved any history anymore.

It only started working after I ran "touch ~/.php_history" to create an empty file. From then on, PHP is saving history again!

I thought this was a bit unusual. Normally, applications recreate their history files themselves. But just be aware of the fact that PHP works this way instead, guys and girls! :-)

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Gray ¶

4 years ago

When adding colours, don't forget that PHP uses the same 'readline' as Bash does, so it has the same need to wrap all colour codes in special marker characters.

If you simply add raw colour codes to the prompt, you will notice that long lines no longer get wrapped correctly -- Readline no longer knows how wide the prompt is.

To fix this, you need to start each colour code with an '0x01' byte (aka Ctrl-A aka SOH) and end it with the '0x02' byte (aka Ctrl-B aka STX). There are no escapes for these -- you have to literally put the control characters in your php-cli.ini.

For example:

<?php

// cli.prompt = <SOH>\e[1m<STX> PHP! \> <SOH>\e[m<STX>

echo "cli.prompt = \x01\\e[1m\x02 PHP! \x01\\e[m\x02\n";
?>

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turabgarip at gmail dot com ¶

7 months ago

Note that destructors will not be triggered when exiting interactive shell by any method. (Like CTRL + D, CTRL + Z or CTRL + C).

Since the interactive shell is effectively a continuous runtime, the "end of script" condition is never met for a destructor to run. And exiting the interactive shell is not considered end of script but rather the end of interpreter process. And since the process is dead; it can't run the destructor.

Therefore the only way for a destructor to run is that you remove all the references to the corresponding object. Like:

<?php

class A {
    public function __destructor() {
        // This will never run after ending PHP interactive shell session.
    }
}

$a = new A();

// This is the only way for the destructor to be able to run.
$a = null; // Or;
unset($a);

?>