vrb_init(3)

πŸ“¦ version 0.5.1, in nixos 26.05

πŸ¦‹ NAME πŸ¦‹

okay bestie, this is vrb_init(3) from the VRB Programmer's Manual: vrb_init β€” initialize a virtual ring buffer πŸ’–

πŸ“š LIBRARY πŸ“š

you get this one by linking with -lvrb ✨

🌈 SYNOPSIS 🌈

here's the exact summoning ritual, no cap:

#include <vrb.h>

vrb_p vrb_init(vrb_p vrb, size_t size, const char *name);

πŸŽ€ DESCRIPTION πŸŽ€

so vrb_init initializes a static or pre-allocated virtual ring buffer structure. that's the main-character job πŸ’…

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 β€” which eliminates the need to split any sequence to handle a buffer wraparound. literally iconic, no wrapping-induced splitting drama πŸ¦‹

πŸ’œ ARGUMENTS πŸ’œ

  • vrb_p vrb β€” specifies the virtual ring buffer structure to be initialized. the caller must release buffer resources via vrb_uninit(3) when this virtual ring buffer is no longer needed. if NULL is given, a new virtual ring buffer structure is allocated, and then the caller must release buffer resources via vrb_destroy(3) when an allocated virtual ring buffer is no longer needed 🫢
  • size_t size β€” 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, so 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 β€” 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; otherwise 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) 🌸

πŸ”₯ RETURN VALUE πŸ”₯

  • vrb_p β€” on success, a handle (pointer) to the newly created virtual ring buffer is returned. on error, NULL is returned 😭

πŸ’€ ERRORS πŸ’€

if an error is returned, then errno will have one of the following values:

  • EINVAL β€” a buffer size was requested which is too large for address space allocation arithmetic πŸ™ˆ
  • ENOMEM β€” out of memory allocating the virtual ring buffer structure πŸ’€
  • - β€” an errno value set by a failing system call ⚠️

🌟 SEE ALSO 🌟

go check out the whole squad: 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_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_len(3), vrb_space_ptr(3), vrb_take(3), vrb_uninit(3), vrb_write(3), vrb_write_min(3) πŸ‘‘


that's the whole page, bestie 🫢 β€” this cutie comes from vrb, dated 2002-09-30, and the manual page is vrb_init(3) πŸ’…βœ¨

πŸ“¦ where this page comes from