Write words to a port
#include <hw/inout.h> void * out16s( const void * buff, unsigned len, uintptr_t port );
libc
Use the -l c option to qcc to link against this library. This library is usually included automatically.
The out16s() function writes len words from the buffer pointed to by buff to the specified port.
The calling process must use mmap_device_io() to access the device's I/O registers.
On x86 and x86_64 targets, the process must have the PROCMGR_AID_IO ability enabled, and the calling thread must have I/O privileges, or else it will fault with a SIGSEGV; see procmgr_ability(), and the ThreadCtl() _NTO_TCTL_IO command.
A pointer to the end of the written data.
Safety: | |
---|---|
Cancellation point | No |
Interrupt handler | Yes |
Signal handler | Yes |
Thread | Yes |