in16s()
QNX SDP8.0C Library ReferenceAPIDeveloper
Read 16-bit values from a port
Synopsis:
#include <hw/inout.h>
void * in16s( void * buff,
unsigned len,
uintptr_t port );
Arguments:
- buff
- A pointer to a buffer where the function can store the values read.
- len
- The number of values that you want to read.
- port
- The port you want to read the values from.
Library:
libc
Use the -l c option to qcc to link against this library. This library is usually included automatically.
Description:
The in16s() function reads len 16-bit values from the specified port and stores them in the buffer pointed to by buff.
The calling process must use mmap_device_io() to access the device's I/O registers.
On x86_64 targets, the process must have the PROCMGR_AID_IO ability enabled, and calling thread must have I/O privileges, or else it will fault with a SIGSEGV; see procmgr_ability(), and the ThreadCtl() _NTO_TCTL_IO_LEVEL command.
Returns:
A pointer to the end of the read data.
Classification:
| Safety: | |
|---|---|
| Cancellation point | No |
| Signal handler | Yes |
| Thread | Yes |
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