The behaviour of these functions is affected by settings in php.ini.
| Name | Default | Changeable | Changelog | 
|---|---|---|---|
| ignore_user_abort | "0" | PHP_INI_ALL | |
| highlight.string | "#DD0000" | PHP_INI_ALL | |
| highlight.comment | "#FF8000" | PHP_INI_ALL | |
| highlight.keyword | "#007700" | PHP_INI_ALL | |
| highlight.bg | "#FFFFFF" | PHP_INI_ALL | Removed in PHP 5.4.0. | 
| highlight.default | "#0000BB" | PHP_INI_ALL | |
| highlight.html | "#000000" | PHP_INI_ALL | |
| browscap | NULL | PHP_INI_SYSTEM | 
Here's a short explanation of the configuration directives.
ignore_user_abort
     boolean
    
      FALSE by default. If changed to TRUE scripts will not be terminated
      after a client has aborted their connection.
     
See also ignore_user_abort().
highlight.bg
      string
     highlight.comment
      string
     highlight.default
      string
     highlight.html
      string
     highlight.keyword
      string
     highlight.string
      string
     Colors for Syntax Highlighting mode. Anything that's acceptable in <font color="??????"> would work.
browscap
     string
    Name (e.g.: browscap.ini) and location of browser capabilities file. See also get_browser().