When booting the system, truncate the utx.active file, but do write the
BOOT_TIME record into it afterwards. This allows one to obtain the boot
time of the system as follows:
struct utmpx u1 = { .ut_type = BOOT_TIME }, *u2;
setutxent();
u2 = getutxid(&u1);
Now, the boot time is stored in u2->ut_tv, just like on Linux and other
systems.
We don't open the utx.active file with O_EXLOCK. It's rather unlikely
that other applications use this database at the same time and I want to
prevent the possibility of deadlocks in init(8).
Discussed with: pluknet
working MI one. The MI one only needs to be overridden on machines
with non-IEEE754 arithmetic. (The last supported one was the VAX.)
It can also be overridden if someone comes up with a faster one that
actually passes the regression tests -- but this is harder than it sounds.
- Handle cases where exp(x) would overflow, but ccosh(x) ~= exp(x) / 2
shouldn't.
- Use the ccosh(x) ~= exp(x) / 2 approximation to simplify the calculation
when x is large.
Similarly for csinh(). Also fixed the return value of csinh(-Inf +- 0i).
exp(x) scaled down by some factor, and the challenge is doing this
accurately when exp(x) would overflow. This change replaces all of
the tricks we've been using with common __ldexp_exp() and
__ldexp_cexp() routines that handle all the scaling.
bde plans to improve on this further by moving the guts of exp() into
k_exp.c and handling the scaling in a more direct manner. But the
current approach is simple and adequate for now.
As the underlying block is 4KB if the PMC throughput is low the measurement
will be reported on the next tick. pmcstat(8) use the modified flush API to
reclaim current buffer before displaying next top.
MFC after: 1 month
library," since complex.h, tgmath.h, and fenv.h are also part of the
math library. Replace the outdated sentence with some references to
the other parts.
and the caller requested other process' PID by passing non-NULL pidptr
argument, we will wait at most 100ms for the PID to show up in the file and if
it won't, we will store -1 in *pidptr.
From now on, pidfile_open() function never sets errno to EAGAIN on failure.
In collaboration with: des
MFC after: 1 week
- Rename __kernel_log() to k_log1p().
- Move some of the work that was previously done in the kernel log into
the callers. This enables further refactoring to improve accuracy or
speed, although I don't recall the details.
- Use extra precision when adding the final scaling term, which improves
accuracy.
- Describe and work around compiler problems that break some of the
multiprecision calculations.
A fix for a small bug is also included:
- Add a special case for log*(1). This is needed to ensure that log*(1) == +0
instead of -0, even when the rounding mode is FE_DOWNWARD.
Submitted by: bde
no longer "fast" on sparc64. (It really wasn't to begin with, since
the old implementation was using long doubles, and long doubles are
emulated in software on sparc64.)
round-to-nearest mode when the result, rounded to twice machine
precision, was exactly halfway between two machine-precision
values. The essence of the fix is to simulate a "sticky bit" in
the pathological cases, which is how hardware implementations
break the ties.
MFC after: 1 month
libusb_dev_kernel_driver_active() works. In case of
libusb20 the manpage was wrong and in case of
libusb10 the implementation was wrong.
Submitted by: Kai Wang
MFC after: 3 days
fenv.h that are currently inlined.
The definitions are provided in fenv.c via 'extern inline'
declaractions. This assumes the compiler handles 'extern inline' as
specified in C99, which has been true under FreeBSD since 8.0.
The goal is to eventually remove the 'static' keyword from the inline
definitions in fenv.h, so that non-inlined references all wind up
pointing to the same external definition like they're supposed to.
I am deferring the second step to provide a window where
newly-compiled apps will still link against old math libraries.
(This isn't supported, but there's no need to cause undue breakage.)
Reviewed by: stefanf, bde
