According to the format of the output file, the macro package defines a given symbol:
  • latex when the output format is LaTeX,
  • html when the output format is HTML,
  • man when the output format is groff in conjunction with the man macro package,
  • ms when the output format is groff with the ms package,
  • sgml when the output format is SGML,
  • txt when the output format is plain ASCII.
    • The defined symbol can be tested in a document to determine the conversion type. Furthermore, the package defines the following macros to send litteral text (commands in the output format) to the output file:
  • latexcommand(cmd): sends the LaTeX command cmd when in LaTeX conversion mode. The cmd is not further expanded.
  • htmlcommand(cmd): sends the HTML command cmd when in HTML conversion mode. The cmd is not further expanded.
  • htmltag(tag)(onoff): sends <tag> to the output when onoff is nonzero, or sends </tag> when onoff is zero. Only active in HTML conversions.
  • mancommand(cmd): sends cmd to the output when in man conversion mode. The cmd is not further expanded.
  • mscommand(cmd): sends cmd to the output when in ms conversion mode. The cmd is not further expanded.
  • roffcmd(dotcmd)(trailer)(secondline)(thirdline): sends a command to the output when in man or ms conversion mode. The dotcmd is the typical groff command that starts with a dot. All other arguments may be empty, but when given are interpreted as follows. The trailer follows the dotcmd on the same line. The secondline is sent on a separate line following the dotcmd and trailer. The thirdline is sent after that. Of the four arguments, dotcmd and thirdline are not subject to further expansion. All other arguments are further expanded if necessary. The roffcmd macro illustrates the complexity of dot-commands for the divers groff macro packages. E.g., a section title for the man package should look as 
    .SH "Section Title"

    while the same command for the ms macro package must be sent as 

    .SH
Section Title
.PP

    The roffcmd macro can be used to send these commands to the output file as follows: 

    COMMENT(For the man output format:)
roffcmd(.SH)("Section Title")()()

COMMENT(For the ms output format:)
roffcmd(.SH)()(Section Title)(.PP)()

  • sgmlcommand(cmd): sends the SGML command cmd when in SGML conversion mode. The cmd is not further expanded.

  • sgmltag(tag)(onoff): sends <tag> when onoff is nonzero, or sends </tag> when onoff is zero. Only active in SGML conversions.

  • txtcommand(cmd): implemented for compatibility reasons, though a `command' in plain ASCII output doesn't make much sense. The usefulness of this macro is rather in the fact that it only produces output when in ASCII conversion mode.

    • The above commands can be used to quickly implement a macro. E.g., the macro package implements the it macro (which starts an item in a list) as: 

    DEFINEMACRO(it)(0)(\ 
        latexcommand(\item )\ 
        htmlcommand(<li> )\ 
        ....)

    Depending on the output format, it() will lead to one of the above expansions.

    The above described formatcommand() macros are implemented to send not further expanded strings (i.e., commands) to the output. The macro package also implements whenformat() macros to send any text, which is then subject to further expansion. These when...() macros are:

  • whenlatex(text): sends text when in LaTeX conversion mode,

  • whenhtml(text): sends text when in HTML conversion mode,

  • whenman(text): sends text when in man conversion mode,

  • whenms(text): sends text when in ms conversion mode,

  • whentxt(text): sends text when in ASCII conversion mode,

  • whensgml(text): sends text when in SGML conversion mode.

    • Note again that the difference between the whenformat() macros and the formatcommand() macros is, that the former will expand their argument while the latter will not. As an example, consider the following code fragment: 

    You are now reading
        whenlatex(a LaTeX-generated 
                  footnote(LaTeX is a great 
		           document language!)
                  document)
        whenhtml(a HTML document via your
                 favorite browser)

    The whenformat() macros are used here to make sure that the arguments to the macros are further expanded; this makes sure that the footnote macro in the whenlatex block gets treated as a footnote.

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    Copyright (c) 1997, 1998, 1999 Karel Kubat and Jan Nieuwenhuizen.

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