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vrb_space_len(3) [debian man page]

vrb_space_len(3)					      VRB Programmer's Manual						  vrb_space_len(3)

NAME
vrb_space_len - return the length of space LIBRARY
-lvrb SYNOPSIS
#include <vrb.h> size_t vrb_space_len(vrb_p vrb); DESCRIPTION
vrb_space_len returns the total length of space available in the given virtual ring buffer. This is the maximum space the caller may store into the buffer from the pointer returned by vrb_space_ptr(3). ARGUMENTS
vrb_p vrb specifies the virtual ring buffer to obtain the length of available space in. If a NULL or invalid pointer is given, results are unpre- dictable and are likely to be disasterous. RETURN VALUE
size_t The length of available space in the virtual ring buffer is returned. 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_resize(3), vrb_space_ptr(3), vrb_take(3), vrb_uninit(3), vrb_write(3), vrb_write_min(3) vrb 2002-09-30 vrb_space_len(3)

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vrb_new(3)						      VRB Programmer's Manual							vrb_new(3)

NAME
vrb_new - create a new virtual ring buffer LIBRARY
-lvrb SYNOPSIS
#include <vrb.h> vrb_p vrb_new(size_t size, const char *name); DESCRIPTION
vrb_new creates a new instance of a virtual ring buffer. A virtual ring buffer is a character FIFO queue with the special property that any sequence of characters in the buffer may be accessed as a single contiguous block of memory, eliminating the need to split any sequence to handle a buffer wraparound. ARGUMENTS
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 temporary name pattern or an actual 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 name string ends in "XXXXXX" then mkstemp(3) will be used to make the file unique. Other- wise it will be used as is. If the named file already exists or otherwise 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
vrb_p On success, a handle (pointer) to the newly created virtual ring buffer is returned. On error, NULL is returned. ERRORS
If an error is returned, then errno will have one of the following values: 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_opt(3), vrb_put(3), vrb_put_all(3), vrb_read(3), vrb_read_min(3), vrb_resize(3), vrb_space_len(3), vrb_space_ptr(3), vrb_take(3), vrb_uninit(3), vrb_write(3), vrb_write_min(3) vrb 2002-09-30 vrb_new(3)
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