Functions in this library provide most of the interfaces specified by the POSIX.1b Realtime Extension. See standards(5). Specifically, this includes the interfaces defined under the Asynchronous I/O, Message Passing, Process Scheduling, Realtime Signals Extension, Semaphores, Shared Memory Objects, Synchronized I/O, and Timers options. The interfaces defined under the Memory Mapped Files, Process Memory Locking, and Range Memory Locking options are provided in libc(3LIB).

See the man pages for the individual interfaces in section 3RT for information on required headers.

The name libposix4 is maintained for backward compatibility and should be avoided. librt is the preferred name for this library.

The shared objects librt.so.1 and libposix4.so.1 provide the public interfaces defined below. See intro(3) for additional information on shared object interfaces.

The following interfaces are unique to the 32-bit version of this library:

/usr/lib/librt.so.1

shared object

/usr/lib/64/librt.so.1

64-bit shared object file

/usr/lib/libposix4.so.1

shared object

/usr/lib/64/libposix4.so.1

64-bit shared object file

See attributes(5) for descriptions of the following attributes:

pvs(1), intro(3), libc(3LIB), attributes(5), standards(5)