狗爺語錄

I had a so-called “poll” on Win32 PHP (chinese only), which actually was simply a nag of problems writing code on PHP with cross-platform support (Windows and Linux are in my mind), especially when dealing with file system and command execution — without telling in detail. The complaint had been well hidden in another blog post, but since I don’t want to dive into unconstructive criticism, I just refrain from posting the whole thing here without digging into detail. Until now. That’s lucky, as some more information is revealed, and the situation is not as crappy as I expected. Here goes the first one.

Problem executing commands with more than 2 double quotes

The most frequently used command execution functions in PHP include exec(), system() and so on. They have a common problem: no more than 2 double quotes allowed. For example:

<?php system('"C:\Program Files\ImageMagick\display.exe" "C:\Document and Settings\user\Great Pic.jpg"'); ?>

Such commands are actually pretty common, with space in program path as well as arguments that followed. Regardless of program execution privilege or whatever, the system() itself already fails.

People used to know this for 2 years or more, yet no cure exists. Funny schemes were invented to circumvent such problem, there are at least 2 on PHP website comments:

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