7.64. V4L2 munmap()

7.64.1. Name

v4l2-munmap - Unmap device memory

7.64.2. Synopsis

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

int munmap(void *start, size_t length)

7.64.3. 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.

7.64.4. Description

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

7.64.5. 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.