in grotty(1). This makes it possible to view colorized manpages in
color.
When MANPAGER environment variable is set, use it instead of PAGER.
Why another environment variable, one might ask? With color output
enabled, both a terminal and a pager should support the ANSI color
escapes. On a supporting terminal, less(1) with option -R would be
such a pager, while "more -s" (the current default pager for man(1))
will show garbage. It means a different default pager is needed when
color output is enabled, but many people have PAGER set customary,
and it's unlikely to support ANSI color escapes, so introducing yet
another variable (MANPAGER) seemed like a good option to me:
- if MANPAGER is set, use that unconditionally;
- if you disable color support (it is by default), and don't set
MANPAGER, you get an old behavior: -P pager, $PAGER, "more -s",
in that order;
- if you enable color support (by setting MANCOLOR), and don't set
MANPAGER, we ignore PAGER which is unlikely to support ANSI color
escapes, and you get: -P pager, "less -Rs", in that order;
- you might have good reasons for different man(1) and general
purpose pagers;
- later versions of GNU man(1) support MANPAGER.
If set to a numeric value, used as the width manpages should be
displayed. Otherwise, if set to a special value ``tty'', and
output is to a terminal, the pages may be displayed over the
whole width of the screen.
commandline. This mirrors the old (undocumented) GNU man functionality.
Also document this feature in the implementation notes section of
the manpage.
Submitted by: arundel
Approved by: wes (mentor implicit)
Features of this new version in favor of the old one:
BSD licensed -- old one is GPL.
Imports configuration from /etc/man.conf and LOCALBASE/etc/man.d/*.conf
allowing ports to extend the base functionality. The pluggable
configuration can supplement the manual search path (retiring use.perl),
add locales, and override language specific toolsets (attempt to merge
the japanese/man port into the base system as much as possible).
Much effort has been made to make this version mirror the functionality
of the existing implementation. For 99% of users, it should be a drop in
replacement.
PR: gnu/143271, gnu/4419
Reviewed by: dougb (previous versions)
Approved by: wes (mentor)
