Use snprintf(3) in place of unbounded sprintf(3) (prevent buffer overflow).
Use adequately sized buffer for error(s) (512 -> PATH_MAX + 512).
Fix the following style(9) nits while here:
- distfetch.c uses PATH_MAX while distextract.c uses MAXPATHLEN;
  standardize on one (PATH_MAX)
- Move $FreeBSD$ from comment to __FBSDID()
- Sort included headers (alphabetically, sys/* at top)
- Add missing header includes (e.g., <stdlib.h> for getenv(3),
  calloc(3)/malloc(3)/free(3), and atoi(3); <string.h> for strdup(3),
  strrchr(3), strsep(3), and strcmp(3); <ctype.h> for isspace(3); and
  <unistd.h> for chdir(2), etc.)
- Remove rogue newline at end of distfetch.c
- Don't declare variables in if-, while-, or other statement
NB: To prevent masking of prior declarations atop function
- Perform stack alignment for variable declarations
- Add missing function prototype for count_files() in distextract.c
- Break out single-line multivariable-declarations
NB: Aligning similarly-named variables with one-char difference(s)
NB: Minimizes diffs and makes future diffs more clear
- Use err(3) family of functions (requires s/int err;/int retval;/g)

Reviewed by:	nwhitehorn, julian
Instead of failing when neither PAM_TTY nor PAM_RHOST are available, call
login_access() with "**unknown**" as the second argument.  This will allow
"ALL" rules to match.

Reported by:	Tim Daneliuk <tundra@tundraware.com>
Tested by:	dim@
PR:		83099 193927
MFC after:	3 days
Hopefully fix build breakage with gcc passing void * instead of char *
to "%s" format string after r272280.

PR:		83099 193927
MFC after:	3 days
X-MFC with:	r272280
Search for the nearest PORTSDIR where Mk/bsd.ports.mk exists, from .CURDIR.
This will only take effect if PORTSDIR is not set, as previously supported.

Use .if exists(), for four specific possibilities relative to .CURDIR:
., .., ../.., and ../../..  The fourth possibility is primarily in case
ports ever grows a third level.  If none of these paths exist, fall back to
the old default of /usr/ports.

This removes the need to set PORTSDIR explicitly (or via wrapper script) if
one is running out of a ports tree that is not in /usr/ports, but in a
home directory.

Reviewed by:	bapt, bdrewery (older version)
CR:		D799
MFC after:	1 week
Sponsored by:	Spectra Logic
Fix integer truncation in affecting systat -ifstat

The "systat -ifstat" command was using a u_int to store byte counters.
With a 10Gbps or faster interface, this overflows within the default
5 second refresh period.  Switch to using a uint64_t across the board,
which matches the size used for all counters as of r263102.

PR:		182448
MFC after:	1 week
Sponsored by:	Sandvine Inc
Ensure that ixl_flush() uses a defined register on VFs

In some code that is shared between the ixl(4) and ixlv(4) drivers,
a macro hard-coded a register offset that was not valid on ixlv devices.
Fix this by having each driver define a variable that contains the correct
offset.

Reviewed by:	Eric Joyner <ricera10 AT gmail.com>
MFC after:	3 days
Sponsored by:	Sandvine Inc
When setting environment variables in the atrun script, use the
"export foo=bar" form instead of "foo=bar; export foo" since the
former allows the shell to catch variable names that are not valid
shell identifiers.  This will cause /bin/sh to exit with an error
(which gets mailed to the at user) and it will not run the script.

Obtained from:	OpenBSD (r1.63 millert)
MFC after:	3 days
Sigh, remove a line that needs to be removed along with previous commit.

Submitted by:	mjg
MFC after:	3 days
X-MFC-with:	272288
Use bzero instead of explicitly zeroing stuff in do_execve.

While strictly speaking this is not correct since some fields are pointers,
it makes no difference on all supported archs and we already rely on it doing
the right thing in other places.

No functional changes.
Document [EPERM] for UNIX sockets.

MFC after:	2 weeks