Rich Felker
1e7f0fcd7f
since time64 switchover has changed the size and layout of the struct anyway, take the opportunity to fix it up so that it can be shared between 32- and 64-bit ABIs on the same system as long as byte order matches. the ut_type member is explicitly padded to make up for m68k having only 2-byte alignment; explicit padding has no effect on other archs. ut_session is changed from long to int, with endian-matched padding. this affects 64-bit archs as well, but brings the type into alignment with glibc's x86_64 struct, so it should not break software, and does not break on-disk format. the semantic type is int (pid-like) anyway. the padding produces correct alignment for the ut_tv member on 32-bit archs that don't naturally align it, so that ABI matches 64-bit. this type is presently not used anywhere in the ABI between libc and libc consumers; it's only used between pairs of consumers if a third-party utmp library using the system utmpx.h is in use.
musl libc
musl, pronounced like the word "mussel", is an MIT-licensed
implementation of the standard C library targetting the Linux syscall
API, suitable for use in a wide range of deployment environments. musl
offers efficient static and dynamic linking support, lightweight code
and low runtime overhead, strong fail-safe guarantees under correct
usage, and correctness in the sense of standards conformance and
safety. musl is built on the principle that these goals are best
achieved through simple code that is easy to understand and maintain.
The 1.1 release series for musl features coverage for all interfaces
defined in ISO C99 and POSIX 2008 base, along with a number of
non-standardized interfaces for compatibility with Linux, BSD, and
glibc functionality.
For basic installation instructions, see the included INSTALL file.
Information on full musl-targeted compiler toolchains, system
bootstrapping, and Linux distributions built on musl can be found on
the project website:
http://www.musl-libc.org/