7.65. V4L2 munmap()¶

7.65.1. Name¶

v4l2-munmap - Unmap device memory

7.65.2. Synopsis¶

#include <unistd.h>
#include <sys/mman.h>

int munmap(void *start, size_t length)¶

7.65.3. Arguments¶

start: Address of the mapped buffer as returned by the mmap() function.
length: Length of the mapped buffer. This must be the same value as given to mmap() and returned by the driver in the struct v4l2_buffer length field for the single-planar API and in the struct v4l2_plane length field for the multi-planar API.

7.65.4. Description¶

Unmaps a previously with the mmap() function mapped buffer and frees it, if possible.

7.65.5. Return Value¶

On success munmap() returns 0, on failure -1 and the errno variable is set appropriately:

EINVAL: The start or length is incorrect, or no buffers have been mapped yet.