libdill: Structured Concurrency for C

NAME

mrecv - receives a message

SYNOPSIS

#include <libdill.h>

ssize_t mrecv(
    int s,
    void* buf,
    size_t len,
    int64_t deadline);

DESCRIPTION

This function receives message from a socket. It is a blocking operation that unblocks only after entire message is received. There is no such thing as partial receive. Either entire message is received or no message at all.

s: The socket.

buf: Buffer to receive the message 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.

RETURN VALUE

In case of success the function returns size of the received message, in bytes. In case of error it returns -1 and sets errno to one of the values below.

ERRORS

EBADF: Invalid handle.
EBUSY: The handle is currently being used by a different coroutine.
ECANCELED: Current coroutine was canceled.
ECONNRESET: Broken connection.
EINVAL: Invalid argument.
EMSGSIZE: The data won't fit into the supplied buffer.
ENOTSUP: The handle does not support this operation.
EPIPE: Closed connection.
ETIMEDOUT: Deadline was reached.

EXAMPLE

char msg[100];
ssize_t msgsz = mrecv(s, msg, sizeof(msg), -1);