IP_TOS2const
Type of service
Usage
#include <netinet/in.h> /* Definition of IP* constants */ #include <sys/socket.h>
int setsockopt(int sockfd, IPPROTO_IP, IP_TOS, const int *tos, sizeof(int)); int getsockopt(int sockfd, IPPROTO_IP, IP_TOS, int *tos, sizeof(int));
Library
Standard C library (libc, -lc)
Overview
Set or receive the Type-Of-Service (TOS) field that is sent with every IP packet originating from this socket. It is used to prioritize packets on the network.
There are some standard TOS flags defined:
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to minimize delays for interactive traffic, |
|---|---|
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to optimize throughput, |
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to optimize for reliability, |
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should be used for "filler data" where slow transmission doesn't matter. |
At most one of these TOS values can be specified. Other bits are invalid and shall be cleared.
Linux sends IPTOS_LOWDELAY datagrams first by default, but the exact behavior depends on the configured queueing discipline.
Some high-priority levels may require superuser privileges (the CAP_NET_ADMIN capability).
Errors
See IPPROTO_IP(2const). See setsockopt(2). See ip(7).