$OPT{'n'} = '-x -S "%0" %*' unless exists $OPT{'n'};
$OPT{'o'} = '-x -S "%0" %1 %2 %3 %4 %5 %6 %7 %8 %9' unless exists $OPT{'o'};
$OPT{'s'} = '/\\.plx?/' unless exists $OPT{'s'};
-$OPT{'s'} = ($OPT{'s'} =~ m|^/([^/]*)| ? $1 : "\Q$OPT{'s'}\E");
+$OPT{'s'} = ($OPT{'s'} =~ m#^/([^/]*[^/\$]|)\$?/?$# ? $1 : "\Q$OPT{'s'}\E");
my $head;
if( defined( $OPT{'a'} ) ) {
perl $OPT{'n'}
if NOT "%COMSPEC%" == "%SystemRoot%\\system32\\cmd.exe" goto endofperl
if %errorlevel% == 9009 echo You do not have Perl in your PATH.
+ if errorlevel 1 goto script_failed_so_exit_with_non_zero_val 2>nul
goto endofperl
\@rem ';
EOT
=head1 DESCRIPTION
This utility converts a perl script into a batch file that can be
-executed on DOS-like operating systems.
+executed on DOS-like operating systems. This is intended to allow
+you to use a Perl script like regular programs and batch files where
+you just enter the name of the script [probably minus the extension]
+plus any command-line arguments and the script is found in your B<PATH>
+and run.
-Note that by default, the ".pl" suffix will be stripped before adding
-a ".bat" suffix to the supplied file names. This can be controlled
-with the C<-s> option.
+=head2 ADVANTAGES
+
+There are several alternatives to this method of running a Perl script.
+They each have disadvantages that help you understand the motivation
+for using B<pl2bat>.
+
+=over
+
+=item 1
+
+ C:> perl x:/path/to/script.pl [args]
+
+=item 2
+
+ C:> perl -S script.pl [args]
+
+=item 3
+
+ C:> perl -S script [args]
+
+=item 4
+
+ C:> ftype Perl=perl.exe "%1" %*
+ C:> assoc .pl=Perl
+ then
+ C:> script.pl [args]
+
+=item 5
+
+ C:> ftype Perl=perl.exe "%1" %*
+ C:> assoc .pl=Perl
+ C:> set PathExt=%PathExt%;.PL
+ then
+ C:> script [args]
+
+=back
+
+B<1> and B<2> are the most basic invocation methods that should work on
+any system [DOS-like or not]. They require extra typing and require
+that the script user know that the script is written in Perl. This
+is a pain when you have lots of scripts, some written in Perl and some
+not. It can be quite difficult to keep track of which scripts need to
+be run through Perl and which do not. Even worse, scripts often get
+rewritten from simple batch files into more powerful Perl scripts in
+which case these methods would require all existing users of the scripts
+be updated.
+
+B<3> works on modern Win32 versions of Perl. It allows the user to
+omit the ".pl" or ".bat" file extension, which is a minor improvement.
+
+B<4> and B<5> work on some Win32 operating systems with some command
+shells. One major disadvantage with both is that you can't use them
+in pipelines nor with file redirection. For example, none of the
+following will work properly if you used method B<4> or B<5>:
+
+ C:> script.pl <infile
+ C:> script.pl >outfile
+ C:> echo y | script.pl
+ C:> script.pl | more
+
+This is due to a Win32 bug which Perl has no control over. This bug
+is the major motivation for B<pl2bat> [which was originally written
+for DOS] being used on Win32 systems.
+
+Note also that B<5> works on a smaller range of combinations of Win32
+systems and command shells while B<4> requires that the user know
+that the script is a Perl script [because the ".pl" extension must
+be entered]. This makes it hard to standardize on either of these
+methods.
+
+=head2 DISADVANTAGES
+
+There are several potential traps you should be aware of when you
+use B<pl2bat>.
+
+The generated batch file is initially processed as a batch file each
+time it is run. This means that, to use it from within another batch
+file you should preceed it with C<call> or else the calling batch
+file will not run any commands after the script:
+
+ call script [args]
+
+Except under Windows NT, if you specify more than 9 arguments to
+the generated batch file then the 10th and subsequent arguments
+are silently ignored.
+
+Except when using F<CMD.EXE> under Windows NT, if F<perl.exe> is not
+in your B<PATH>, then trying to run the script will give you a generic
+"Command not found"-type of error message that will probably make you
+think that the script itself is not in your B<PATH>. When using
+F<CMD.EXE> under Windows NT, the generic error message is followed by
+"You do not have Perl in your PATH", to make this clearer.
+
+On most DOS-like operating systems, the only way to exit a batch file
+is to "fall off the end" of the file. B<pl2bat> implements this by
+doing C<goto :endofperl> and adding C<__END__> and C<:endofperl> as
+the last two lines of the generated batch file. This means:
+
+=over
+
+=item No line of your script should start with a colon.
+
+In particular, for this version of B<pl2bat>, C<:endofperl>,
+C<:WinNT>, and C<:script_failed_so_exit_with_non_zero_val> should not
+be used.
+
+=item Care must be taken when using C<__END__> and the C<DATA> file handle.
+
+One approach is:
+
+ #!perl
+ while( <DATA> ) {
+ last if /^__END__$/;
+ [...]
+ }
+ __END__
+ lines of data
+ to be processed
+ __END__
+ :endofperl
+
+=item The batch file always "succeeds"
+
+The following commands illustrate the problem:
+
+ C:> echo exit(99); >fail.pl
+ C:> pl2bat fail.pl
+ C:> perl -e "print system('perl fail.pl')"
+ 99
+ C:> perl -e "print system('fail.bat')"
+ 0
+
+So F<fail.bat> always reports that it completed successfully. Actually,
+under Windows NT, we have:
+
+ C:> perl -e "print system('fail.bat')"
+ 1
+
+So, for Windows NT, F<fail.bat> fails when the Perl script fails, but
+the return code is always C<1>, not the return code from the Perl script.
+
+=back
+
+=head2 FUNCTION
+
+By default, the ".pl" suffix will be stripped before adding a ".bat" suffix
+to the supplied file names. This can be controlled with the C<-s> option.
The default behavior is to have the batch file compare the C<OS>
environment variable against C<"Windows_NT">. If they match, it
uses the C<%*> construct to refer to all the command line arguments
that were given to it, so you'll need to make sure that works on your
-variant of the command shell. It is known to work in the cmd.exe shell
-under WindowsNT. 4DOS/NT users will want to put a C<ParameterChar = *>
+variant of the command shell. It is known to work in the F<CMD.EXE> shell
+under Windows NT. 4DOS/NT users will want to put a C<ParameterChar = *>
line in their initialization file, or execute C<setdos /p*> in
the shell startup file.
see runperl.bat for an alternative way to invoke perl scripts.
Default behavior is to invoke Perl with the B<-S> flag, so Perl will
-search the PATH to find the script. This may have undesirable
+search the B<PATH> to find the script. This may have undesirable
effects.
+On really old versions of Win32 Perl, you can't run the script
+via
+
+ C:> script.bat [args]
+
+and must use
+
+ C:> script [args]
+
+A loop should be used to build up the argument list when not on
+Windows NT so more than 9 arguments can be processed.
+
+See also L</Disadvantages>.
+
=head1 SEE ALSO
perl, perlwin32, runperl.bat
projects / p5sagit/p5-mst-13.2.git / commitdiff