NAME

SYNOPSIS

#include <libdill.h>
ssize_t udp_recv(
    int s,
    struct ipaddr* addr,
    void* buf,
    size_t len,
    int64_t deadline);

    

DESCRIPTION

This function receives a single UDP packet.

s: Handle of the UDP socket.

addr: Out parameter. IP address of the sender of the packet. Can be NULL.

buf: Buffer to receive the data to.

len: Size of the buffer, in bytes.

deadline: A point in time when the operation should time out, in milliseconds. Use the now function to get your current point in time. 0 means immediate timeout, i.e., perform the operation if possible or return without blocking if not. -1 means no deadline, i.e., the call will block forever if the operation cannot be performed.

This function is not available if libdill is compiled with --disable-sockets option.

RETURN VALUE

ERRORS

•

EBADF: Invalid handle.

•

EBUSY: The handle is currently being used by a different coroutine.

•

ECANCELED: Current coroutine was canceled.

•

EINVAL: Invalid argument.

•

EMSGSIZE: The data won't fit into the supplied buffer.

•

ENOTSUP: The handle does not support this operation.

•

ETIMEDOUT: Deadline was reached.

EXAMPLE

struct ipaddr local;
ipaddr_local(&local, NULL, 5555, 0);
struct ipaddr remote;
ipaddr_remote(&remote, "server.example.org", 5555, 0, -1);
int s = udp_open(&local, &remote);
udp_send(s1, NULL, "ABC", 3);
char buf[2000];
ssize_t sz = udp_recv(s, NULL, buf, sizeof(buf), -1);
hclose(s);

    

SEE ALSO