Added mkexec.pl

bin/mkexec.pl

@@ -0,0 +1,75 @@
+#!/usr/bin/perl
+# make an executeble file
+
+use strict;
+use warnings;
+
+sub usage; sub mkexec; sub guesstype; sub getcmd; sub launch_editor;
+
+my $DEFAULT_TYPE = 'pl';
+my $DEFAULT_MODE = 0755;
+
+my $name = shift or usage;
+my $type = ($ARGV[0] ? shift : guesstype $name);
+
+my $bang = {
+	pl   => `which perl`,
+	sh   => `which sh`,
+	py   => `which python`,
+	bash => `which bash`,
+	sed  => `which sed`,
+	bc   => `which bc`
+};
+
+my $editors = [ qw/ vim editor / ];
+my $cmds;
+$cmds->{vim}->{test}    = "vim --version 2>/dev/null";
+$cmds->{vim}->{run}     = "vim +\"normal G\$\" '%s'";
+$cmds->{editor}->{test} = "editor --version 2>/dev/null";
+$cmds->{editor}->{run}  = "editor '%s'";
+
+
+if (exists $bang->{$type}) {
+	mkexec $name, $bang->{$type};
+    launch_editor $name;
+} else {
+	die "unknown type: $type\n";
+}
+
+sub usage {
+	print STDERR "usage: $0 filename [type]\n";
+	exit 0;
+}
+
+sub guesstype {
+	my $name = shift;
+	my ($ext) = $name =~ m|\.(\w+)$|;
+	return ( $ext ? $ext : $DEFAULT_TYPE);
+}
+
+sub mkexec {
+	my ($name, $bang) = @_;
+	open EXE, ">", $name	|| die "cannot open $name for writing: $!\n";
+	-W EXE			|| die "file $name is not writable\n";
+	print EXE "#!$bang\n";
+	close EXE		|| die "cannot close $name: $!\n";
+	chmod $DEFAULT_MODE, $name;
+}
+
+sub get_cmd {
+    foreach (@$editors) {
+        return $cmds->{$_}->{run} if `$cmds->{$_}->{test}`
+    }
+    warn "no supported editor available\n";
+    return;
+}
+
+sub launch_editor {
+    my $name = shift;
+    my $form = get_cmd;
+    if ($form) {
+        my $command = sprintf get_cmd, $name;
+        exec "$command";
+    } else { return }
+    warn "failed to launch editor: $form\n";
+}