Function switch_socket_recv 

pub unsafe extern "C" fn switch_socket_recv(
    sock: *mut switch_socket_t,
    buf: *mut c_char,
    len: *mut switch_size_t,
) -> switch_status_t

Read data from a network. @param sock The socket to read the data from. @param buf The buffer to store the data in. @param len On entry, the number of bytes to receive; on exit, the number of bytes received. @remark

This functions acts like a blocking read by default.  To change
this behavior, use fspr_socket_timeout_set() or the APR_SO_NONBLOCK
socket option.
The number of bytes actually received is stored in argument 3.

It is possible for both bytes to be received and an APR_EOF or
other error to be returned.

APR_EINTR is never returned.