To give some context to my question, here is a test program:

use strict;
use warnings;

# Given an ini file, return a string containing section contents.
# (Note that ini file comment lines start with a ;)
sub get_section
{
   my $fcontents = shift;    # in: ini file contents string
   my $section   = shift;    # in: section name to get

   # Note that the regex below will find multiple sections;
   # it's terminated by the start of a new section or end of file.
   my $s = join( "", $fcontents =~ /^[ \t]*\[$section\](.*?)(?:\Z|^[ \
+t]*\[)/msg );

   $s =~ s/^[ \t]+//mg;    # remove leading  whitespace from each line
   $s =~ s/[ \t]+$//mg;    # remove trailing whitespace from each line
   $s =~ s/^\s+//;         # remove leading  whitespace
   $s =~ s/\s+$//;         # remove trailing whitespace

   # Remove up to three trailing comment lines
   $s =~ s/^;.*\Z//m; chomp $s;
   $s =~ s/^;.*\Z//m; chomp $s;
   $s =~ s/^;.*\Z//m; chomp $s;

   return $s;
}

my $inifile_contents = <<'BUK_LIKES_SUNDIALS';
[MySection]
; This is a comment line for MySection
fld1 = 'value of field 1' 
fld2 = 42

; This is the heading for AnotherSection
[AnotherSection]
; another comment
asfld=69
BUK_LIKES_SUNDIALS

my $section1 = get_section( $inifile_contents, 'MySection' );
print "This is the contents of MySection -------\n$section1\n";

my $section2 = get_section( $inifile_contents, 'AnotherSection' );
print "This is the contents of AnotherSection -------\n$section2\n";
[download]

Running the test program above produces:

This is the contents of MySection -------
; This is a comment line for MySection
fld1 = 'value of field 1'
fld2 = 42
This is the contents of AnotherSection -------
; another comment
asfld=69
[download]

I added the code to remove trailing comment lines because I found, in practice, that trailing comment lines in a section tended to be unrelated to that section, rather they were usually header comment lines for the following section.

Though general suggestions for code improvements are welcome, my specific question relates to this eyesore:

# Remove up to three trailing comment lines
$s =~ s/^;.*\Z//m; chomp $s;
$s =~ s/^;.*\Z//m; chomp $s;
$s =~ s/^;.*\Z//m; chomp $s;
[download]