23. Device Control#
23.1. Introduction#
The POSIX Device Control API is defined by POSIX 1003.26 and attempts to provides a portable alternative to the ioctl() service which is not standardized across POSIX implementations. Support for this standard is required by the Open Group’s FACE Technical Standard :cits:“FACE:2012:FTS”. Unfortunately, this part of the POSIX standard is not widely implemented.
The services provided by the timer manager are:
[posix_devctl] - Control a Device
23.2. Background#
23.3. Operations#
23.4. System Calls#
This section details the POSIX device control’s services. A subsection is dedicated to each of this manager’s services and describes the calling sequence, related constants, usage, and status codes.
23.4.1. posix_devctl - Control a Device#
CALLING SEQUENCE:
: #include <devctl.h> int posix_devctl(
int fd, int dcmd, void restrict dev_data_ptr, size_t nbyte, int restrict dev_info_ptr
);
` STATUS CODES:
The status codes returned reflect those returned by the ioctl() service
and the underlying device drivers.
DESCRIPTION:
This method is intended to be a portable alternative to the ioctl()
method. The RTEMS implementation follows what is referred to as a library
implementation which is a simple wrapper for the ioctl() method.
The fd, fcmd, dev_data_ptr, and nbyte parameters are passed unmodified
to the ioctl() method.
If the dev_info_ptr parameter is not NULL, then the location pointed to by dev_info_ptr is set to 0.
NOTES:
NONE