NetBSD's PTHREAD_KEYS_MAX is set to 256, which is low compared to
other systems like Linux (1024) or MacOS X (512). As a result some
setups tested on Linux will exhibit problems on NetBSD because of
pthread_keys usage beyond the limit. This happens for instance on
Apache with various module loaded, and in this case no particular
developper can be blamed for going beyond the limit, since several
modules from different sources contribute to the problem.
This patch makes the limit conigurable through the PTHREAD_KEYS_MAX
environement variable. If undefined, the default remains unchanged
(256). In any case, the value cannot be lowered below POSIX-mandated
_POSIX_THREAD_KEYS_MAX (128).
While there:
- use EXIT_FAILURE instead of 1 when calling err(3) in libpthread.
- Reset _POSIX_THREAD_KEYS_MAX to POSIX mandated 128, instead of 256.
checks. Compared to OpenBSD's reallocarray, makes it easier to avoid memory
leaks on allocation failures and it doesn't depend on malloc(0) != NULL
for correct error checking. Compared to plain realloc, it also avoids
the problem of intermediate integer overflows. The trade-off is the use
of void * to side step C type system with regard to generic pointer to
pointer.
unistd.h and libc, and add a man page.
Allow wiggle room in the man page for implementations of fallocate
that either (a) don't fully unwind on failure, leaving new blocks
allocated without changing the file size, or (b) create only in-memory
transient reservations that disappear when crashing or rebooting.
Also, add crossreference to fdiscard from ftruncate(2), and remove the
old BUGS entry from there that called for a generalized version that
allows discarding ranges of a file: that's what fdiscard is.
that uses rpc needs to define _REENTRANT to work properly. We'll keep
compatibility but setting the old variable in the library, but we are not
advertising it anymore.
