Structure for information from the protocol database
#include <netdb.h> struct protoent { char * p_name; char ** p_aliases; int p_proto; };
The protoent structure holds information from the network protocols database, /etc/protocols. The members of this structure are:
endprotoent(), getprotobyname(), getprotobynumber(), getprotoent(), setprotoent()
/etc/protocols in the Utilities Reference