endservent, getservbyport, getservbyname, getservent, setservent - network services database functions
#include <netdb.h>
void endservent(void);
struct servent *getservbyname(const char *name, const char *proto);
struct servent *getservbyport(int port, const char *proto);
struct servent *getservent(void);
void setservent(int stayopen);
Thegetservbyname() ,getservbyport() andgetservent() functions each return a pointer to a servent structure, the members of which contain the fields of an entry in the network services database.The
getservent() function reads the next entry of the database, opening a connection to the database if necessary.The
getservbyname() function searches the database from the beginning and finds the first entry for which the service name specified by name matches the s_name member and the protocol name specified by proto matches the s_proto member, opening a connection to the database if necessary. If proto is a null pointer, any value of the s_proto member will be matched.The
getservbyport() function searches the database from the beginning and finds the first entry for which the port specified by port matches the s_port member and the protocol name specified by proto matches the s_proto member, opening a connection to the database if necessary. If proto is a null pointer, any value of the s_proto member will be matched. The port argument must be in network byte order.The
setservent() function opens a connection to the database, and sets the next entry to the first entry. If the stayopen argument is non-zero, the net database will not be closed after each call to thegetservent() function (either directly, or indirectly through one of the othergetserv*() functions).The
endservent() function closes the database.
On successful completion,getservbyname() ,getservbyport() andgetservent() return a pointer to a servent structure if the requested entry was found, and a null pointer if the end of the database was reached or the requested entry was not found. Otherwise, a null pointer is returned.
No errors are defined.
The port argument ofgetservbyport() need not be compatible with the port values of all address families.The
getservent() ,getservbyname() andgetservbyport() functions may return pointers to static data, which may be overwritten by subsequent calls to any of these functions.
endhostent() ,endprotoent() ,htonl() ,inet_addr() ,<netdb.h> .
First released in Issue 4.
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