Configuring The System - PHP

If what you're really after involves reading configuration variables in from a standard .INI file, you don't need to write custom code to parse the file and read in the variable-value pairs. Instead, just use PHP's
parse_ini_file() function, which automatically takes care of this for you.

Consider the following sample .INI file,

[global]

printing = bsd

default case = lower

log file = /var/log/samba/log.%m

printcap name = /etc/printcap

max log size = 50

domain master = yes

dns proxy = no

[temp]

comment = Temporary file space

path = /tmp

read only = no

public = yes

create mask = 0777

force group = nobody

force user = nobody

and the PHP code to parse it:

<?php

// set file to read

$filename = "samba.ini";
// read INI file into array

$data = parse_ini_file($filename);
// print array

print_r($data);
?>

A quick glance at the output shows that PHP has, indeed, read the file, parsed its contents, and converted the variable-value pairs into an associative array.

Array
(
[printing] => bsd
[default case] => lower
[log file] => /var/log/samba/log.%m
[printcap name] => /etc/printcap
[max log size] => 50
[domain master] => 1
[dns proxy] =>
[comment] => Temporary file space
[path] => /tmp
[read only] =>
[public] => 1
[create mask] => 0777
[force group] => nobody
[force user] => nobody
)

The only problem with the approach, however, is that variables with the same name from different sections will override each other; if there are multiple configuration variables with the same name, the output array will always contain only the last value. In order to illustrate, look what happens when I add a new section to the sample file above which repeats some of the variables from a previous section:

[global]

printing = bsd

default case = lower

log file = /var/log/samba/log.%m

printcap name = /etc/printcap

max log size = 50

domain master = yes

dns proxy = no

[temp]

comment = Temporary file space

path = /tmp

read only = no

public = yes

create mask = 0777

force group = nobody

force user = nobody



[shared]

comment = Shared area

path = /shared

printable = no

create mode = 0770

directory mode = 0770

writeable = yes

Here's the output:

Array
(
[printing] => bsd
[default case] => lower
[log file] => /var/log/samba/log.%m
[printcap name] => /etc/printcap
[max log size] => 50
[domain master] => 1
[dns proxy] =>
[comment] => Shared area
[path] => /shared
[read only] =>
[public] => 1
[create mask] => 0777
[force group] => nobody
[force user] => nobody
[printable] =>
[create mode] => 0770
[directory mode] => 0770
[writeable] => 1
)

As you can see, some of the variable-value pairs (from the "temp" section of the file) have been lost. PHP offers a solution to this problem by allowing a second, optional argument to parse_ini_file() - a Boolean indicating whether the namespaces of the various sections should be respected. When I add that to the script above,

<?php

// set file to read

$filename = "samba.ini";
// read INI file into array

// process each section separately

$data = parse_ini_file($filename, true);
// print array

print_r($data);
?>

look how drastically the output changes:

Array
(
[global] => Array
(
[printing] => bsd
[default case] => lower
[log file] => /var/log/samba/log.%m
[printcap name] => /etc/printcap
[max log size] => 50
[domain master] => 1
[dns proxy] =>
)

[temp] => Array
(
[comment] => Temporary file space
[path] => /tmp
[read only] =>
[public] => 1
[create mask] => 0777
[force group] => nobody
[force user] => nobody
)

[shared] => Array
(
[comment] => Shared area
[path] => /shared
[printable] =>
[create mode] => 0770
[directory mode] => 0770
[writeable] => 1
)

)

With the addition of the second argument to parse_ini_file(), PHP now creates a nested array, with the outer array referencing the sections, and each inner one referencing the variables in each section.