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Is there a case, when calling of sendto() on UDP socket returns 0 and if yes, what does it mean? Manual only says, that on error it's -1, otherwise it's number of bytes sent.

Youda008
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1 Answers1

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You can send()/sendto() a zero-byte message on a domain datagram or UDP socket, in which case a returned length of 0 bytes is correct. If you are seeing this unexpectedly, verify your len parameter in your sendto(int fd, void const *buf, size_t len, int flags, struct const *dest, sockles_t addrlen) call.

Jeff
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