vrb_write_min(3) write data from a VRB




#include <vrb.h>

size_t vrb_write_min(vrb_p vrb, int fd, size_t maxsize, size_t minsize);


vrb_write_min writes a minimum amount of data to a specified open file descriptor using write(2) from the specified virtual ring buffer until the specified maximum length has been written, the buffer is full, or an error is returned (including EAGAIN or EWOULDBLOCK for a non-blocking descriptor). If there is insufficient data in the buffer to write the minimum amount, then write(2) will not be called.


vrb_p vrb
specifies which virtual ring buffer.

int fd
specifies the open file descriptor to write to

size_t maxsize
specifies the maximum length to write, or ~0 for unlimited.

size_t minsize
specifies the minimum length to write.


If successful, the actual length of data written from the buffer is returned. If the minimum amount of data was not available to be written, 0 is returned. If an error occurs from write(2), the return value is ~0 and errno is set by write(2).


If an error is returned, then errno will have one of the following values:
An end-of-file has occurred. Note that this is a different way of returning an end-of-file condition than write(2) uses.
An invalid virtual ring buffer pointer was specified.