NAME¶
vrb_resize - create a new virtual ring buffer
LIBRARY¶
-lvrb
SYNOPSIS¶
#include <vrb.h>
vrb_p vrb_resize(size_t size, const char
*name);
DESCRIPTION¶
vrb_resize changes the size of a virtual ring buffer if the data in the
source buffer will fit in the requested space.
ARGUMENTS¶
vrb_p vrb
specifies the ring buffer which will be resized.
size_t size
specifies the requested minimum buffer size to be allocated. The given value
will be rounded up to the nearest or equal whole multiple of the system page
size. The virtual ring buffer is implemented by mapping two adjacent blocks of
memory to the same memory object. Thus, twice as much virtual address space
will be used and the specified size must be less than half of the available
virtual address space for this process.
const char *name
specifies an optional name of a file to be used as backing store via
mmap(2) in a mounted filesystem in which the process has write
permission. If the named file cannot be opened for write, an error will occur.
If
NULL is given, swap space will be used as backing store via
shmat(2).
RETURN VALUE¶
int
On success, 0 is returned. Otherwise, -1 is returned.
ERRORS¶
If an error is returned, then
errno will have one of the following
values:
- ENOSPC
- The data in the current virtual ring buffer will not fit
into the requested space.
- EINVAL
- A buffer size was requested which is too large for address
space allocation arithmetic.
- ENOMEM
- Out of memory allocating the virtual ring buffer
structure.
- -
- An errno value set by a failing system call.
SEE ALSO¶
vrb(3),
vrb_capacity(3),
vrb_data_len(3),
vrb_data_ptr(3),
vrb_destroy(3),
vrb_get(3),
vrb_get_min(3),
vrb_give(3),
vrb_init(3),
vrb_init_opt(3),
vrb_is_empty(3),
vrb_is_full(3),
vrb_is_not_empty(3),
vrb_is_not_full(3),
vrb_move(3),
vrb_new(3),
vrb_new_opt(3),
vrb_put(3),
vrb_put_all(3),
vrb_read(3),
vrb_read_min(3),
vrb_space_len(3),
vrb_space_ptr(3),
vrb_take(3),
vrb_uninit(3),
vrb_write(3),
vrb_write_min(3)
