Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Per Regents of the University of Calfornia letter, remove advertising
clause.

# If I've done so improperly on a file, please let me know.

mdoc(7) police: Use the new .In macro for #include statements.

Whitespace only change: trim trailing whitespace.

Modify strtofflags so that it returns a malloced string instead of a
pointer to a static buffer.

The "def" arg for fflagstostr is too specialized for ls. The caller
can easily translate from "" to whatever it wants to print if no
flags are set. (ls prints "-" and mtree prints "none".)

Suggested by: bde

Return of the evil file flags! The {s|g}etflags functions were
renamed to {s|g}etflagsbyname, which received objections. They're
now called strtofflags (string to file flags) and fflagstostr (file
flags to string).

Suggested by: bde

Introduce ".Lb" macro to libc manpages.

More libraries manpages updates following.

Historically file flags (schg, uschg, etc) have been converted from
string to u_long and back using two functions, flags_to_string and
string_to_flags, which co-existed with 'ls'. As time has progressed
more and more other tools have used these private functions to
manipulate the file flags.

Recently I moved these functions from /usr/src/bin/ls to libutil,
but after some discussion with bde it's been decided that they
really ought to go in libc.

There are two already existing libc functions for manipulating file
modes: setmode and getmode. In keeping with these flags_to_string
has been renamed getflags and string_to_flags to setflags.

The manual page could probably be improved upon ;)