#!/usr/bin/perl -w

use Fcntl qw(:DEFAULT :flock);
use File::Temp qw(tempfile);
use File::Spec;

my $editor = $ENV{EDITOR} || 'vi';

# for naming temp files, so can chase down which app they are coming
# from if problems crop up
my ($ourname) = $0 =~ /([\w.-]+)$/;
$ourname ||= 'perl';

File::Temp->safe_level(2);
my ($tfh, $fname) =
 tempfile("$ourname.XXXXXXX", DIR => File::Spec->tmpdir, UNLINK => 1);

# set autoflush to ensure editor gets the right data
my $oldfh = select $tfh;
$| = 1;
select $oldfh;

print $tfh <<"INTRO";
Default text to appear in editor.
INTRO

# File::Temp locks the file by default, which is not productive
# with external editors that also want to lock the file.
flock $tfh, LOCK_UN;

my $status = system "$editor $fname";
die "external editor failed with $?\n" unless $status == 0;

# deal with supplied data
seek $tfh, 0, 0 or die "Error seeking on temp file: $!\n";
while (<$tfh>) {
  print;
}
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