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PHPDBG is a built-in PHP debugger that can be used to debug PHP code and performance.
While less well-known than other debuggers such as Xdebug, it can be a valuable tool for understanding what’s happening behind the scenes in your PHP code.
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Enable PHPDBG Enable PHPDBG
In order to use PHPDBG, you must first enable it by compiling PHP with the --enable-debug option.
You can do this by downloading the PHP source code and compiling it yourself,
Or, by using a pre-compiled package that has PHPDBG enabled.
Start PHPDBG Start PHPDBG
To start PHPDBG, you can use the phpdbg command followed by the name of the PHP script you want to debug.
For example:
$ phpdbg script.php
Enter interactive mode Enter interactive mode
When PHPDBG starts, it will enter interactive mode, allowing you to enter commands and inspect the state of your PHP code.
Set breakpoints Set breakpoints
To set a breakpoint in your code, use the b command followed by the line number.
For example:
phpdbg> b 10
This will set a breakpoint on line 10 of your PHP script.
Start execution Start execution
To start executing your PHP script, use the r command.
PHPDBG will run until it reaches a breakpoint or until the script finishes executing.
phpdbg> r
Inspect variables Inspect variables
While your script is paused at a breakpoint, you can inspect variables and their values using the p command.
For example:
phpdbg> p $variable
This will print the value of the variable named $variable.
Step through code Step through code
You can step through your code line by line using the s command.
This will allow you to see how the values of variables change as your script executes.
phpdbg> s
Continue execution Continue execution
When you’re ready to continue executing your script, use the c command.
This will resume execution until the next breakpoint or until the script finishes executing.
phpdbg> c
Quit PHPDBG Quit PHPDBG
To exit PHPDBG and stop debugging, use the q command.
phpdbg> q
These are the basic steps for using PHPDBG to debug PHP code.
By using breakpoints, inspecting variables, and stepping through code, you can gain a deeper understanding of what’s happening behind the scenes in your PHP scripts.
Conclusion Conclusion
These are the basic steps for using PHPDBG to debug PHP code.
By using breakpoints, inspecting variables, and stepping through code, you can gain a deeper understanding of what’s happening behind the scenes in your PHP scripts.