gnutls_record_send_file3

Arguments

gnutls_session_t session

is a gnutls_session_t type.

int fd

file descriptor from which to read data.

off_t * offset

Is relative to file offset, denotes the starting location for reading. after function returns, it point to position following last read byte.

size_t count

is the length of the data in bytes to be read from file and send.

Overview

This function sends data from fd . If KTLS (kernel TLS) is enabled, it will use the sendfile() system call to avoid overhead of copying data between user space and the kernel. Otherwise, this functionality is merely emulated by calling read() and gnutls_record_send(). If this implementation is suboptimal, check whether KTLS is enabled using gnutls_transport_is_ktls_enabled().

If offset is NULL then file offset is incremented by number of bytes send, otherwise file offset remains unchanged.

Returns

The number of bytes sent, or a negative error code.