Some applications, notably PostgreSQL, want to call setproctitle()
very often. It's slow. Provide an alternative cheap way of updating
process titles without making any syscalls, instead requiring other
processes (top, ps etc) to do a bit more work to retrieve the data.
This uses a pre-existing code path inherited from ancient BSD, which
always did it that way.
Submitted by: Thomas Munro
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D16111
Although groff_mdoc(7) gives another impression, this is the ordering
most widely used and also required by mdocml/mandoc.
Reviewed by: ru
Approved by: philip, ed (mentors)
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
Install (optional) libutil.h with prototypes for the functions and
document this in the man page.
minor cleanups to the various routines, include the prototype file, declare
return codes etc.
replace the dozen other various hacks in the code that do all sorts
of crude things including spamming the envrionment strings with the new
argv string.
This version is mainly inspired by the sendmail version, with a couple of
ideas taken from the NetBSD implementation as well.
