Solution using Path::Tiny which writes the new file alongside the existing file, then does an atomic rename. See Re^2: Yet another config file editing programme : Tell me how to make it better ! and Re^3: Yet another config file editing programme : Tell me how to make it better !
#!/usr/bin/perl
use strict; # https://perlmonks.org/?node_id=11136353
use warnings;
use Path::Tiny;
my $dhcpcdfile = 'fake.353'; # FIXME filename
-w $dhcpcdfile or die "cannot write $dhcpcdfile";
my %ip_params = (
interface => "usb0",
ip_address => "1.1.1.0",
routers => "127.0.0.0",
domain_servers => "1.1.1.1"
);
%ip_params = ( %ip_params, # add new data to defaults
path('inputfile.353')->slurp =~ /^(\w+)=(.*?)\s*$/gm ); # FIXME file
+name
my $foundinterface = 0;
path( $dhcpcdfile )->edit_lines( sub
{
if( /^\s*profile\s+static_$ip_params{interface}\b.*\n/m ) # alter th
+is section
{
$foundinterface = 1;
}
elsif( $foundinterface and /^\s*static/m )
{
s/^\s*static\s+(\w+)=\K.*/$ip_params{$1}/m or die "failed to chang
+e $1";
}
elsif( $foundinterface )
{
$foundinterface = 0;
}
} );