size_t vrb_write_min(vrb_p vrb, int fd, size_t maxsize, size_t minsize);
writes a minimum amount of data to a specified open file descriptor
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,
will not be called.
specifies which virtual ring buffer.
specifies the open file descriptor to write to
specifies the maximum length to write, or
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
the return value is ~0 and
errno is set by
If an error is returned, then
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
An invalid virtual ring buffer pointer was specified.