Defined in 2 files as a macro:

• sys/contrib/ipfilter/netinet/ip_compat.h, line 845 (as a macro)
• sys/netinet/tcp.h, line 90 (as a macro)

Referenced in 8 files:

• contrib/ipfilter/lib/tcpoptnames.c, line 17
• sys/contrib/ipfilter/netinet/ip_compat.h, line 844
• sys/contrib/ipfilter/netinet/ip_state.c, line 1946
• sys/netinet/tcp_input.c, line 3319
• sys/netinet/tcp_output.c, line 1680
• sys/netpfil/ipfw/ip_fw2.c, line 361
• sys/netpfil/pf/pf.c, line 3109
• sys/netpfil/pf/pf_osfp.c, line 165