@c -*-texinfo-*-
@node Invoking LilyPond
@chapter Invoking LilyPond

This chapter details the technicalities of running LilyPond.

 
@menu
* Invoking lilypond::           Titling LilyPond scores.
* Invoking the lilypond binary::  
* Error messages::              
* Reporting bugs::              
* Point and click::             
@end menu

@node Invoking lilypond
@section Invoking lilypond

Nicely titled output is created through a separate program:
@file{@code{lilypond}} is a script that uses the LilyPond formatting
engine (which is in a separate program) and La@TeX{} to create a
nicely titled piece of sheet music, in PDF (Portable Document Format)
format.

@example
        @code{lilypond} [@var{option}]@dots{} @var{file}@dots{}
@end example

To have @code{lilypond} read from stdin, use a dash @code{-} for @var{file}.

The @code{lilypond} program supports the following options:

@table @code
@item -k,--keep
    Keep the temporary directory with all output
files. The temporary directory is created in the current directory as @code{@code{lilypond}.dir}.
@item -d,--dependencies
    Write @code{Makefile} dependencies for every input file.
@item -h,--help
    Print usage help.
@item -I,--include=@var{dir}
    Add @var{dir} to LilyPond's include path.
@item -m,--no-paper
    Produce MIDI output only.
@item --no-lily
    Do not run @file{lilypond-bin}. Useful for debugging @code{lilypond}.
@item -o,--output=@var{file}
    Generate output to @var{file}.  The extension of @var{file} is ignored.
@item --no-pdf
    Do not generate  (PDF) or PS.

@cindex PDF
@cindex Scalable fonts
    
@c why is this comment here? --hwn

        If you use lilypond-book or your own wrapper files, do not use
@code{\usepackage[[T1]@{fontenc@}} in the file header but do not forget
@code{\usepackage[latin1]@{inputenc@}} if you use any other
non-anglosaxian characters.

@item --png
    Also generate pictures of each page, in PNG format. 
@item --psgz
    Gzip the postscript file.
@item --html
    Make a .HTML file with links to all output files.
@item --preview
    Also generate a picture of the first system of the score.

@cindex preview
@cindex picture
@cindex bitmap
@cindex pixmap
@cindex thumbnail
@cindex screenshot
    
@item -s,--set=@var{key}=@var{val}
    Add @var{key}= @var{val} to the settings, overriding those specified
in the files. Possible keys: @code{language}, @code{latexheaders},
@code{latexpackages}, @code{latexoptions}, @code{papersize},
@code{pagenumber}, @code{linewidth}, @code{orientation},
@code{textheight}.
@item -v,--version
Show version information.
@item -V,--verbose
Be verbose.
@item --debug
Print even more information. This is useful when generating bugreports.
@item -w,--warranty
Show the warranty with which GNU LilyPond comes. (It comes with 
@strong{NO WARRANTY}!)
@end table

@subsection Titling layout

@code{lilypond} extracts the following header fields from the LY files
to generate titling; an example demonstrating all these fields is in
@inputfileref{input/test,ly2dvi-testpage.ly}:

@table @code
@item title
    The title of the music. Centered on top of the first page.
@item subtitle
    Subtitle, centered below the title.
@item poet
    Name of the poet, left flushed below the subtitle.
@item composer
    Name of the composer, right flushed below the subtitle.
@item meter
    Meter string, left flushed below the poet.
@item opus
    Name of the opus, right flushed below the composer.
@item arranger
    Name of the arranger, right flushed below the opus.
@item instrument
    Name of the instrument, centered below the arranger.
@item dedication            
    To whom the piece is dedicated.
@item piece
    Name of the piece, left flushed below the instrument.
@item head
    A text to print in the header of all pages. It is not called
@code{header}, because @code{\header} is a reserved word in LilyPond.
@item copyright
    A text to print in the footer of the first page. Default is to 
    print the standard footer also on the first page.
@item footer
    A text to print in the footer of all but the last page.
@item tagline
    Line to print at the bottom of last page. The default text is ``Lily
was here, @var{version-number}''.
@end table


@cindex header
@cindex footer
@cindex page layout
@cindex titles



@subsection Additional parameters

The @code{lilypond} program responds to several parameters specified
in a @code{\paper} section of the input file. They can be overridden
by supplying a @code{--set} command line option.

@table @code
@item language
    Specify La@TeX{} language: the @code{babel} package will be
included.  Default: unset.

        Read from the @code{\header} block.

@item latexheaders
    Specify additional La@TeX{} headers file.

        Normally read from the @code{\header} block. Default value: empty.

@item latexpackages
    Specify additional La@TeX{} packages file. This works cumulative,
so you can add multiple packages using multiple @code{-s=latexpackages} options.
       Normally read from the @code{\header} block. Default value:
@code{geometry}.

@item latexoptions
    Specify additional options for the La@TeX{}
@code{\documentclass}. You can put any valid value here. This was
designed to allow @code{lilypond} to produce output for double-sided
paper, with balanced margins and pagenumbers on alternating sides. To
achieve this specify @code{twoside}.

@item orientation
    Set orientation. Choices are @code{portrait} or @code{landscape}. Is
read from the @code{\paper} block, if set.
        
@item textheight
    The vertical extension of the music on the page. It is normally 
    calculated automatically, based on the paper size.

@item linewidth
        The music line width. It is normally read from the @code{\paper}
block.

@item papersize
   The paper size (as a name, e.g. @code{a4}). It is normally read from
the @code{\paper} block.

@item pagenumber
   If set to @code{no}, no page numbers will be printed.  If set to a
positive integer, start with this value as the first page number.

  
  @item fontenc
     The font encoding, should be set identical to the @code{font-encoding}
     property in the score.
@end table



@node Invoking the lilypond binary
@section Invoking the lilypond binary
@cindex Invoking LilyPond
@cindex command line options
@cindex options, command line
@cindex switches


The LilyPond system consists of two parts: a binary executable, which
is responsible for the formatting functionality, and support scripts,
which post-process the resulting output. Normally, the support scripts
are called, which in turn invoke the @code{lilypond-bin}
binary. However, @code{lilypond-bin} may be called directly as
follows.

@example
        lilypond-bin [@var{option}]@dots{} @var{file}@dots{}
@end example


When invoked with a filename that has no extension, the @file{.ly}
extension is tried first.  To read input from  stdin, use a
dash @code{-} for @var{file}.

When @file{filename.ly} is processed it will produce
@file{filename.tex} as output (or @file{filename.ps} for PostScript
output).  If @file{filename.ly} contains more than one @code{\score}
block, then the rest of the scores will be output in numbered files,
starting with @file{filename-1.tex}.  Several files can be specified;
they will each be processed independently.  @footnote{The status of
  GUILE is not reset across invocations, so be careful not to change any
  system defaults from within Scheme.}


@section Command line options

The following options are supported:

@table @code

@item -e,--evaluate=@var{expr}
Evaluate the Scheme @var{expr} before parsing any @file{.ly} files.
Multiple @code{-e} options may be given, they will be evaluated
sequentially.  The function @code{ly:set-option} allows for access to
some internal variables.  Use @code{-e '(ly:option-usage')} for more
information.

@item -f,--format=@var{format}
@c
@c
Output format for sheet music. Choices are @code{tex} (for @TeX{}
output, to be processed with plain @TeX{}, or through @code{lilypond}),
@code{pdftex} for PDF@TeX{} input, @code{ps} (for PostScript),
@code{scm} (for a Scheme dump), @code{sk} (for Sketch) and @code{as}
(for ASCII-art).

@strong{This option is only for developers}. Only the @TeX{} output of
these is usable for real work.


@cindex output format, setting
@cindex Sketch output
@cindex ASCII-art output
@cindex PDFTeX output
@cindex PostScript output
@cindex Scheme dump

@item -h,--help
Show a summary of usage.
@item --include, -I=@var{directory}
Add @var{directory} to the search path for input files.
@cindex file searching
@cindex search path
@item -i,--init=@var{file}
Set init file to @var{file} (default: @file{init.ly}).
@item -m,--no-paper
@cindex MIDI
Disable @TeX{} output. If you have a @code{\midi} definition MIDI output
will be generated.
@item -M,--dependencies
Output rules to be included in Makefile.
@item -o,--output=@var{FILE}
Set the default output file to @var{FILE}.

@ignore
@item -s,--safe
Disallow untrusted @code{\include} directives, in-line
Scheme evaluation, backslashes in @TeX{}, code.

@strong{WARNING}: the @code{--safe} option has not been reviewed for a
long time. Do not rely on it for automatic invocation (e.g. over the
web). Volunteers are welcome to do a new audit.
@end ignore

@item -v,--version
Show version information.
@item -V,--verbose
Be verbose: show full paths of all  files read, and give timing
information.

@item -w,--warranty
Show the warranty with which GNU LilyPond comes. (It comes with 
@strong{NO WARRANTY}!)
@end table

@section Environment variables


For processing both the @TeX{} and the PostScript output, the
appropriate environment variables must be set.  The following scripts
do this:

@itemize @bullet
@item @file{buildscripts/out/lilypond-profile}
(for SH shells)
@item  @file{buildscripts/out/lilypond-login} (for C-shells)
@end itemize

They should normally be sourced as part of the login process. If these
scripts are not run from the system wide login process, then you must
run it yourself.

@cindex installing LilyPond

If you use sh, bash, or a similar shell, then add the following to
your @file{.profile}:
@example
	. @var{/the/path/to/}lilypond-profile
@end example

If you use csh, tcsh or a similar shell, then add the following to
your @file{~/.login}:
@example
	source @var{/the/path/to/}lilypond-login
@end example

Of course, in both cases, you should substitute the proper location of
either script.

These scripts set the following variables:
@table @code
@item TEXMF
 To make sure that @TeX{} and lilypond find data files (among
others @file{.tex}, @file{.mf} and @file{.tfm}),
you have to set @code{TEXMF} to point to the lilypond data
file tree. A typical setting would be
@example
@{/usr/share/lilypond/1.6.0,@{!!/usr/share/texmf@}@}
@end example


@item GS_LIB
For processing PostScript output (obtained with
@code{-f ps}) with Ghostscript you have to set @code{GS_LIB} to
point to the directory containing library PS files.

@item GS_FONTPATH
For processing PostScript output (obtained with
@code{-f ps}) with Ghostscript you have to set @code{GS_FONTPATH} to
point to the directory containing  PFA files.

When you print direct PS output, remember to send the PFA files to the
printer as well.
@end table


@cindex ghostscript
@cindex PostScript
@cindex GS_FONTPATH
@cindex GS_LIB
@cindex TEXMF
@cindex printing postscript

The  binary itself recognizes the following environment variables:
@table @code
@item LILYPONDPREFIX
This specifies a directory where locale messages and
data files will be looked up by default. The directory should contain
subdirectories called @file{ly/}, @file{ps/}, @file{tex/}, etc.

@item LANG
This selects the language for the warning messages.
@end table

@cindex LANG
@cindex LILYPONDPREFIX

@node Error messages
@section Error messages

@cindex error messages
Different error messages can appear while compiling a file:

@table @emph
@cindex warning

@item Warning
  Something looks suspect. If you are requesting something out of the
ordinary then you will understand the message, and can ignore it.
However, warnings usually indicate that something is wrong with the
input file.

@item Error
Something is definitely wrong.  The current processing step (parsing,
interpreting, or formatting) will be finished, but the next step will
be skipped.

@cindex error
@cindex fatal error
@item Fatal error
Something is definitely wrong, and LilyPond cannot continue. This
happens rarely. The most usual cause is misinstalled fonts.

@cindex call trace
@cindex Scheme error
@item Scheme error
Errors that occur while executing Scheme code are caught by the Scheme
interpreter. If running with the verbose option (@code{-V} or
@code{--verbose}) then a call trace is printed of the offending
function call.

@cindex Programming error
@item Programming error
There was some internal inconsistency. These error messages are
intended to help the programmers and debuggers. Usually, they can be
ignored. Sometimes, they come in such big quantities that they obscure
other output. In this case, a bug-report should be filed.

@end table

@cindex errors, message format
If warnings and errors can
be linked to some part of the input file, then error messages have the
following form

@example
  @var{filename}:@var{lineno}:@var{columnno}: @var{message}
  @var{offending input line}
@end example 

A line-break is inserted in offending line to indicate the column
where the error was found. For example, 

@example
test.ly:2:19: error: not a duration: 5:
  \notes @{ c'4 e'5 
                   g' @}
@end example


@node Reporting bugs
@section Reporting bugs

@cindex bugs
@cindex reporting bugs

If you have input that results in a crash or an erroneous output, then
that is a bug. We try respond to bug-reports promptly, and fix them as
soon as possible. For this, we need to reproduce and isolate the
problem. Help us by sending a defective input file, so we can
reproduce the problem. Make it small, so we can easily debug the
problem. Don't forget to tell which version you use, and on which
platform you run it.  Send the report to
@email{bug-lilypond@@gnu.org}.

@node Point and click
@section Point and click
@cindex poind and click

Point and click lets you find notes in the input by clicking on them in
the Xdvi window. This makes it easier to find input that causes some
error in the sheet music.

To use it, you need the following software:
@itemize @bullet
@item a dvi viewer that supports src specials:
@itemize @bullet
@item Xdvi, version 22.36 or newer.  Available from
@uref{ftp://ftp.math.berkeley.edu/pub/Software/TeX/xdvi.tar.gz,ftp.math.berkeley.edu}.

   Most @TeX{} distributions ship with xdvik, which is always
  a few versions behind the official Xdvi. To find out which Xdvi you
  are running, try @code{xdvi -version} or @code{xdvi.bin -version}.
@item KDVI.  A dvi viewer for KDE.  You need KDVI from KDE 3.0 or
newer.  Enable option @emph{Inverse search} in the menu @emph{Settings}.

Apparently, KDVI does not process PostScript specials correctly. Beams
and slurs will not be visible in KDVI.

@cindex Xdvi
@cindex KDVI
@cindex KDE



@end itemize
@item an editor with a client/server interface (or a lightweight GUI
editor):

@cindex editor

@itemize @bullet
@item Emacs. Emacs is an extensible text-editor.  It is available from
@uref{http://www.gnu.org/software/emacs/}.  You need version 21 to use
column location.

@c move this elsewhere?

There is also support for Emacs: lilypond-mode for Emacs provides
keyword autocompletion, indentation, LilyPond specific parenthesis
matching and syntax coloring, handy compile short-cuts and reading
LilyPond manuals using Info.  If lilypond-mode is not installed on
your platform, then refer to the installation instructions for more
information.

@cindex Emacs
@cindex Emacs mode
@cindex lilypond-mode for Emacs
@cindex syntax coloring

@item XEmacs. XEmacs is very similar to Emacs.

@cindex XEmacs

@item NEdit.  NEdit runs under Windows, and Unix.
  It is available from @uref{http://www.nedit.org}.

@cindex NEdit

@item GVim.  GVim is a GUI variant of VIM, the popular VI
clone.  It is available from @uref{http://www.vim.org}.

@cindex GVim
@cindex Vim

@end itemize
@end itemize


Xdvi must be configured to find the @TeX{} fonts and music
fonts. Refer to the Xdvi documentation for more information.

To use point-and-click, add one of these lines to the top of your .ly
file:
@example
#(ly:set-point-and-click 'line)
@end example
@cindex line-location

When viewing, Control-Mousebutton 1 will take you to the originating
spot in the @file{.ly} file.  Control-Mousebutton 2 will show all
clickable boxes.

If you correct large files with point-and-click, be sure to start
correcting at the end of the file. When you start at the top, and
insert one line, all following locations will be off by a line.

@cindex Emacs
For using point-and-click with Emacs,  add the following
In your Emacs startup file (usually @file{~/.emacs}):
@example
(server-start)
@end example

Make sure that the environment variable @var{XEDITOR} is set to
@example
emacsclient --no-wait +%l %f
@end example
@cindex @var{XEDITOR}
If you use XEmacs instead of Emacs, you use @code{(gnuserve-start)} in
your @file{.emacs}, and set @code{XEDITOR} to @code{gnuclient -q +%l %f}.

For using Vim, set @code{XEDITOR} to @code{gvim --remote +%l %f}, or
use this argument with Xdvi's @code{-editor} option.

@cindex NEdit
For using NEdit, set @code{XEDITOR} to @code{nc -noask +%l %f}, or
use this argument with Xdvi's @code{-editor} option.

If can also make your editor jump to the exact location of the note
you clicked. This is only supported on Emacs and VIM. Users of Emacs version
20 must apply the patch @file{emacsclient.patch}. Users of version 21
must apply @file{server.el.patch} (version 21.2 and earlier).  At the
top of the @code{ly} file, replace the @code{set-point-and-click} line
with the following line:
@example
#(ly:set-point-and-click 'line-column)
@end example
@cindex line-colomn-location
and set @code{XEDITOR} to @code{emacsclient --no-wait +%l:%c %f}.  Vim
users can set @var{XEDITOR} to @code{gvim --remote +:%l:norm%c| %f}.



@refbugs

When you convert the @TeX{} file to PostScript using @code{dvips}, it
will complain about not finding @code{src:X:Y} files. These complaints
are harmless, and can be ignored.



