NAME
Shell::Config::Generate - Portably generate config for any shell
VERSION
version 0.17
SYNOPSIS
With this start up:
use Shell::Guess;
use Shell::Config::Generate;
my $config = Shell::Config::Generate->new;
$config->comment( 'this is my config file' );
$config->set( FOO => 'bar' );
$config->set_path(
PERL5LIB => '/foo/bar/lib/perl5',
'/foo/bar/lib/perl5/perl5/site',
);
$config->append_path(
PATH => '/foo/bar/bin',
'/bar/foo/bin',
);
This:
$config->generate_file(Shell::Guess->bourne_shell, 'config.sh');
will generate a config.sh file with this:
# this is my config file
FOO='bar';
export FOO;
PERL5LIB='/foo/bar/lib/perl5:/foo/bar/lib/perl5/perl5/site';
export PERL5LIB;
if [ -n "$PATH" ] ; then
PATH=$PATH:'/foo/bar/bin:/bar/foo/bin';
export PATH
else
PATH='/foo/bar/bin:/bar/foo/bin';
export PATH;
fi;
and this:
$config->generate_file(Shell::Guess->c_shell, 'config.csh');
will generate a config.csh with this:
# this is my config file
setenv FOO 'bar';
setenv PERL5LIB '/foo/bar/lib/perl5:/foo/bar/lib/perl5/perl5/site';
test "$?PATH" = 0 && setenv PATH '/foo/bar/bin:/bar/foo/bin' || setenv PATH "$PATH":'/foo/bar/bin:/bar/foo/bin';
and this:
$config->generate_file(Shell::Guess->cmd_shell, 'config.cmd');
will generate a config.cmd (Windows cmd.exe script) with this:
rem this is my config file
set FOO=bar
set PERL5LIB=/foo/bar/lib/perl5;/foo/bar/lib/perl5/perl5/site
if defined PATH (set PATH=%PATH%;/foo/bar/bin;/bar/foo/bin) else (set PATH=/foo/bar/bin;/bar/foo/bin)
DESCRIPTION
This module provides an interface for specifying shell configurations
for different shell environments without having to worry about the
arcane differences between shells such as csh, sh, cmd.exe and
command.com.
It does not modify the current environment, but it can be used to
create shell configurations which do modify the environment.
This module uses Shell::Guess to represent the different types of
shells that are supported. In this way you can statically specify just
one or more shells:
#!/usr/bin/perl
use Shell::Guess;
use Shell::Config::Generate;
my $config = Shell::Config::Generate->new;
# ... config config ...
$config->generate_file(Shell::Guess->bourne_shell, 'foo.sh' );
$config->generate_file(Shell::Guess->c_shell, 'foo.csh');
$config->generate_file(Shell::Guess->cmd_shell, 'foo.cmd');
$config->generate_file(Shell::Guess->command_shell, 'foo.bat');
This will create foo.sh and foo.csh versions of the configurations,
which can be sourced like so:
#!/bin/sh
. ./foo.sh
or
#!/bin/csh
source foo.csh
It also creates .cmd and .bat files with the same configuration which
can be used in Windows. The configuration can be imported back into
your shell by simply executing these files:
C:\> foo.cmd
or
C:\> foo.bat
Alternatively you can use the shell that called your Perl script using
Shell::Guess's running_shell method, and write the output to standard
out.
#!/usr/bin/perl
use Shell::Guess;
use Shell::Config::Generate;
my $config = Shell::Config::Generate->new;
# ... config config ...
print $config->generate(Shell::Guess->running_shell);
If you use this pattern, you can eval the output of your script using
your shell's back ticks to import the configuration into the shell.
#!/bin/sh
eval `script.pl`
or
#!/bin/csh
eval `script.pl`
CONSTRUCTOR
Shell::Config::Generate->new
creates an instance of She::Config::Generate.
METHODS
There are two types of instance methods for this class:
* modifiers
adjust the configuration in an internal portable format
* generators
generate shell configuration in a specific format given the internal
portable format stored inside the instance.
The idea is that you can create multiple modifications to the
environment without worrying about specific shells, then when you are
done you can create shell specific versions of those modifications
using the generators.
This may be useful for system administrators that must support users
that use different shells, with a single configuration generation
script written in Perl.
$config->set( $name => $value )
Set an environment variable.
$config->set_path( $name => @values )
Sets an environment variable which is stored in standard 'path' format
(Like PATH or PERL5LIB). In UNIX land this is a colon separated list
stored as a string. In Windows this is a semicolon separated list
stored as a string. You can do the same thing using the set method, but
if you do so you have to determine the correct separator.
This will replace the existing path value if it already exists.
$config->append_path( $name => @values );
Appends to an environment variable which is stored in standard 'path'
format. This will create a new environment variable if it doesn't
already exist, or add to an existing value.
$config->prepend_path( $name => @values );
Prepend to an environment variable which is stored in standard 'path'
format. This will create a new environment variable if it doesn't
already exist, or add to an existing value.
$config->comment( $comment )
This will generate a comment in the appropriate format.
note that including comments in your configuration may mean it will not
work with the eval backticks method for importing configurations into
your shell.
$config->shebang( [ $location ] )
This will generate a shebang at the beginning of the configuration,
making it appropriate for use as a script. For non UNIX shells this
will be ignored. If specified, $location will be used as the
interpreter location. If it is not specified, then the default location
for the shell will be used.
note that the shebang in your configuration may mean it will not work
with the eval backticks method for importing configurations into your
shell.
$config->echo_off
For DOS/Windows configurations (command.com or cmd.exe), issue this as
the first line of the config:
@echo off
$config->echo_on
Turn off the echo off (that is do not put anything at the beginning of
the config) for DOS/Windows configurations (command.com or cmd.exe).
$config->set_alias( $alias => $command )
Sets the given alias to the given command.
Caveat: some older shells do not support aliases, such as the original
bourne shell. This module will generate aliases for those shells
anyway, since /bin/sh may actually be a more modern shell that DOES
support aliases, so do not use this method unless you can be reasonable
sure that the shell you are generating supports aliases. On Windows,
for PowerShell, a simple function is used instead of an alias so that
arguments may be specified.
$config->set_path_sep( $sep )
Use $sep as the path separator instead of the shell default path
separator (generally : for Unix shells and ; for Windows shells).
Not all characters are supported, it is usually best to stick with the
shell default or to use : or ;.
$config->generate( [ $shell ] )
Generate shell configuration code for the given shell. $shell is an
instance of Shell::Guess. If $shell is not provided, then this method
will use Shell::Guess to guess the shell that called your perl script.
$config->generate_file( $shell, $filename )
Generate shell configuration code for the given shell and write it to
the given file. $shell is an instance of Shell::Guess. If there is an
IO error it will throw an exception.
FUNCTIONS
win32_space_be_gone( @path_list )
On MSWin32 and cygwin:
Given a list of directory paths (or filenames), this will return an
equivalent list of paths pointing to the same file system objects
without spaces. To do this Win32::GetShortPathName() is used on to find
alternative path names without spaces.
In addition, on just Cygwin:
The input paths are first converted from POSIX to Windows paths using
Cygwin::posix_to_win_path, and then converted back to POSIX paths using
Cygwin::win_to_posix_path.
Elsewhere:
Returns the same list passed into it
CAVEATS
The test suite tests this module's output against the actual shells
that should understand them, if they can be found in the path. You can
generate configurations for shells which are not available (for example
cmd.exe configurations from UNIX or bourne configurations under
windows), but the test suite only tests them if they are found during
the build of this module.
The implementation for csh depends on the external command test. As far
as I can tell test should be available on all modern flavors of UNIX
which are using csh. If anyone can figure out how to prepend or append
to path type environment variable without an external command in csh,
then a patch would be appreciated.
The incantation for prepending and appending elements to a path on csh
probably deserve a comment here. It looks like this:
test "$?PATH" = 0 && setenv PATH '/foo/bar/bin:/bar/foo/bin' || setenv PATH "$PATH":'/foo/bar/bin:/bar/foo/bin';
* one line
The command is all on one line, and doesn't use if, which is probably
more clear and ideomatic. This for example, might make more sense:
if ( $?PATH == 0 ) then
setenv PATH '/foo/bar/bin:/bar/foo/bin'
else
setenv PATH "$PATH":'/foo/bar/bin:/bar/foo/bin'
endif
However, this only works if the code interpreted using the csh source
command or is included in a csh script inline. If you try to invoke
this code using csh eval then it will helpfully convert it to one
line and if does not work under csh in one line.
There are probably more clever or prettier ways to append/prepend path
environment variables as I am not a shell programmer. Patches welcome.
Only UNIX (bourne, bash, csh, ksh, fish and their derivatives) and
Windows (command.com, cmd.exe and PowerShell) are supported so far.
Fish shell support should be considered a tech preview. The Fish shell
itself is somewhat in flux, and thus some tests are skipped for the
Fish shell since behavior is different for different versions. In
particular, new lines in environment variables may not work on newer
versions.
Patches welcome for your favorite shell / operating system.
AUTHOR
Graham Ollis <plicease@cpan.org>
COPYRIGHT AND LICENSE
This software is copyright (c) 2012 by Graham Ollis.
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.