apple: Add RLIMIT_RSS as alias of RLIMIT_AS

This is defined in <sys/resource.h> as

    #define	RLIMIT_RSS	RLIMIT_AS	/* source compatibility alias */

See http://opensource.apple.com//source/xnu/xnu-1456.1.26/bsd/sys/resource.h

This is defined in <sys/resource.h> as

    #define	RLIMIT_RSS	RLIMIT_AS	/* source compatibility alias */

See http://opensource.apple.com//source/xnu/xnu-1456.1.26/bsd/sys/resource.h

OS X: add various process status tests defined by wait.h

Adds the various process test macros specified in the wait(2) manpage on OS X. ```WCOREDUMP``` is implemented BSD-wide as it seems to be the only macro whose definition is constant across the BSDs.

linux: Add prlimit(2) and prlimit64(2)

As with `getrlimit` and `setrlimit`, the glibc wrappers have a non-`int`
for the `resource` argument, eg:

    extern int prlimit (__pid_t __pid, enum __rlimit_resource __resource,
                        const struct rlimit *__new_limit,
                        struct rlimit *__old_limit) __THROW;

As with `getrlimit` and `setrlimit`, the glibc wrappers have a non-`int`
for the `resource` argument, eg:

    extern int prlimit (__pid_t __pid, enum __rlimit_resource __resource,
                        const struct rlimit *__new_limit,
                        struct rlimit *__old_limit) __THROW;

notbsd: Deduplicate definitions

A bunch of definitions were duplicated across, eg, android and linux.
This commit pulls these up to higher levels where they can be shared.

Add SIGEMT (for apple) and SIGINFO (for bsd).

Explain about the automated tests on Travis

in order to advise contributors to locally test their patches.

A bunch of definitions were duplicated across, eg, android and linux.
This commit pulls these up to higher levels where they can be shared.

in order to advise contributors to locally test their patches.

Also update ctest to include a fix on rerun-if-changed so that human
developers doing trial & error can properly test their latest code.

Signed-off-by: NODA, Kai <nodakai@gmail.com>

Use rustup to add targets, not manual curl

Add support for arm-unknown-linux-musleabi{,hf} targets.

These targets will be similar to the x86_64-unknown-linux-musl
target, in that they'll use MUSL libc to allow fully static binaries
to be generated. To remain consistent with the naming of existing
ARM targets, as well as with the standard naming of MUSL toolchains,
we'll use `musleabi` and `musleabihf` as the target environment
names (analogous to `gnueabi` and `gnueabihf`).

Most of these changes just extend the special casing for x86_64 MUSL
targets to the ARM ones as well.

These targets will be similar to the x86_64-unknown-linux-musl
target, in that they'll use MUSL libc to allow fully static binaries
to be generated. To remain consistent with the naming of existing
ARM targets, as well as with the standard naming of MUSL toolchains,
we'll use `musleabi` and `musleabihf` as the target environment
names (analogous to `gnueabi` and `gnueabihf`).

Most of these changes just extend the special casing for x86_64 MUSL
targets to the ARM ones as well.

Add ucontext for linux-musl.

It just copy pasted from the linux-other version.

Add the family of printf, scanf functions

snprintf is apparently supported in MSVC since version 14. I'm curious to take the tests for a spin.

64-bit Android timegm fix

On aarch64 and x86_64, `timegm64` does not exist (see [time64.h](https://android.googlesource.com/platform/development/+/797351fd3bbb8fe517afafdd5095fd740387e7a4/ndk/platforms/android-L/include/time64.h)).

See rust-lang-deprecated/time#118 for usage. Since that patch, the time library switched to using libc for `timegm` (rust-lang-deprecated/time@51c0019), and it doesn't build on 64-bit Android. This PR fixes that.

Bump to 0.2.10

Use '&&' on travis, not ';'

Closes #258

Fix CPU_SET and CPU_ISSET

Signed-off-by: NODA, Kai <nodakai@gmail.com>

Use now available link name "signal" instead of "bsd_signal"

On android, the `bsd_signal` is gone, the `signal` is available.

While this is the most obvious solution, I am not sure of a few things:
- How are we going to keep compatibility with older NDKs where `signal` does not exist;
- Was something dependent on this being different on android and thus would break (for example, the rust compiler uses this function, so it may break somewhere).

Fixes #236.

Remove iOS doc links from README

Fixes #243

langinfo bindings and defs

There are many constants defined by langinfo, but we have the
new types, locale_t and nl_item.

We also have several functions, not all of which exist for every
platform:

nl_langinfo
nl_langinfo_l
newlocale
duplocale
freelocale
uselocale
querylocale

Add RTLD_DEFAULT to more platforms

Link to libraries when disabling `use_std`

This crate currently relies on libraries being linked to come from libstd, but
if `use_std` is disabled that's not true! In that case we need to pull in the
libraries ourselves.

Closes rust-lang/rust#32661