cec-ioctl — Control a cec device
#include <sys/ioctl.h>
int ioctl( | int fd, |
int request, | |
void *argp) ; |
fd
File descriptor returned by open()
.
request
CEC ioctl request code as defined in the cec.h header file, for example CEC_ADAP_G_CAPS.
argp
Pointer to a request-specific structure.
Note: this documents the proposed CEC API. This API is not yet finalized and is currently only available as a staging kernel module.
The ioctl()
function manipulates cec device
parameters. The argument fd
must be an open file
descriptor.
The ioctl request
code specifies the cec
function to be called. It has encoded in it whether the argument is an
input, output or read/write parameter, and the size of the argument
argp
in bytes.
Macros and structures definitions specifying cec ioctl requests and their parameters are located in the cec.h header file. All cec ioctl requests, their respective function and parameters are specified in Appendix M, Function Reference.
On success 0 is returned, on error -1 and the errno
variable is set appropriately. The generic error codes are described at the Generic Error Codes chapter.
Request-specific error codes are listed in the individual requests descriptions.
When an ioctl that takes an output or read/write parameter fails, the parameter remains unmodified.