7.68. V4L2 munmap()¶
7.68.1. Name¶
v4l2-munmap - Unmap device memory
7.68.2. Synopsis¶
#include <unistd.h>
#include <sys/mman.h>
-
int munmap(void *start, size_t length)¶
7.68.3. Arguments¶
startAddress of the mapped buffer as returned by the
mmap()function.lengthLength of the mapped buffer. This must be the same value as given to
mmap()and returned by the driver in the structv4l2_bufferlengthfield for the single-planar API and in the structv4l2_planelengthfield for the multi-planar API.
7.68.4. Description¶
Unmaps a previously with the mmap() function mapped
buffer and frees it, if possible.
7.68.5. Return Value¶
On success munmap() returns 0, on failure -1 and the
errno variable is set appropriately:
- EINVAL
The
startorlengthis incorrect, or no buffers have been mapped yet.