#! perl

# Store help text in variable
$syntax = "\nReadINI.pl,  Version 1.10\n";
$syntax = $syntax."Read a value from the specified INI file\n\n";
$syntax = $syntax."Usage:  READINI.PL  \"ini_file\"  \"section\"  \"key\"\n\n";
$syntax = $syntax."Where:           \"ini_file\" is the file name of the INI file to be read\n";
$syntax = $syntax."                 \"section\"  is the section name, without the brackets\n";
$syntax = $syntax."                 \"key\"      is the key whose value must be read\n\n";
$syntax = $syntax."Example: if MYPROG.INI looks like this:\n";
$syntax = $syntax."[Section 1]\n";
$syntax = $syntax."Key1=Value 1\n";
$syntax = $syntax."Key2=Value 2\n";
$syntax = $syntax."[Section 2]\n";
$syntax = $syntax."Key2=Value 3\n";
$syntax = $syntax."[Section 3]\n";
$syntax = $syntax."Key2=Value 4\n";
$syntax = $syntax."Then the command:  READINI.PL  \"MYPROG.INI\"  \"section 2\"  \"key2\"\n";
$syntax = $syntax."should return:     Value 3\n\n";
$syntax = $syntax."Written by Rob van der Woude\n";
$syntax = $syntax."http://www.robvanderwoude.com\n";

# Switch to slurp mode
undef $/;

# Check command line arguments and open INI file
if ( @ARGV[2] ) {
	$ini     = @ARGV[0];
	open( STDIN, "< $ini" ) || die "Cannot open file $ini\n$!\n\n$syntax";
	$section = @ARGV[1];
	$key     = @ARGV[2];
} else {
	die "$syntax";
}

# Changed ([^\n]*\n)* into ([^\[][^\n]*\n)*? after a bug report by Boby Dumoulin
while ( <STDIN> ) {
	if ( $_ =~ m/^\[$section\]\s*\n([^\[][^\n]*\n)*?"?$key"?\s*=\s*"?([^\n]+)"?\s*(\n|$)/im ) {
		print "\n\"$ini\"\n";
		print "[$section]\n";
		print "$key=$2\n";
	}
}

# Close INI file
close STDIN;