NAME

allreadwrite, allreadwritev - perform specified I/O operation until fully completed

SYNOPSIS

#include <limb/allreadwrite.h>

ssize_t (*io_func) (int fd, char *data, size_t dlen)
ssize_t (*iov_func) (int fd, const struct iovec *v, unsigned n)

size_t allreadwrite(io_func op, int fd, char *data, size_t dlen)
size_t allreadwritev(iov_func op, int fd, const struct iovec *v, unsigned n)

DESCRIPTION

The allreadwrite() function will call op with fd, data and dlen as arguments, expecting it to perform the requested I/O operation, returning the amount of bytes read/written on success, or -1 on error (setting errno to indicate the error).

If less than dlen bytes have been processed, it will call op again (updating its arguments data and dlen appropriately), until either dlen bytes have been processed in total, end-of-file has been reached, or an error occurred.

The allreadwritev() function is similar, except that the arguments given to op are fd and the pointer to an internal array of struct iovec and its number of elements, originally similar to v and n but later adjusted as needed. The original array v remains unchanged.

RETURN VALUE

These functions return the number of bytes processed, which may be less than dlen (even 0).