getservbyport

GETSERVENT(3)              Linux Programmer's Manual             GETSERVENT(3)



NAME
       getservent,  getservbyname, getservbyport, setservent, endservent - get
       service entry

SYNOPSIS
       #include <netdb.h>

       struct servent *getservent(void);

       struct servent *getservbyname(const char *name, const char *proto);

       struct servent *getservbyport(int port, const char *proto);

       void setservent(int stayopen);

       void endservent(void);

DESCRIPTION
       The getservent() function reads the next line from the  file  /etc/ser-
       vices  and returns a structure servent containing the broken out fields
       from the line.  The /etc/services file is opened if necessary.

       The getservbyname() function returns a servent structure for  the  line
       from  /etc/services that matches the service name using protocol proto.
       If proto is NULL, any protocol will be matched.

       The getservbyport() function returns a servent structure for  the  line
       that  matches  the port port given in network byte order using protocol
       proto. If proto is NULL, any protocol will be matched.

       The setservent() function opens and rewinds the /etc/services file.  If
       stayopen is true (1), then the file will not be closed between calls to
       getservbyname() and getservbyport().

       The endservent() function closes /etc/services.

       The servent structure is defined in <netdb.h> as follows:

              struct servent {
                      char    *s_name;        /* official service name */
                      char    **s_aliases;    /* alias list */
                      int     s_port;         /* port number */
                      char    *s_proto;       /* protocol to use */
              }

       The members of the servent structure are:

       s_name The official name of the service.

       s_aliases
              A zero terminated list of alternative names for the service.

       s_port The port number for the service given in network byte order.

       s_proto
              The name of the protocol to use with this service.

RETURN VALUE
       The getservent(), getservbyname() and getservbyport() functions  return
       the  servent structure, or a NULL pointer if an error occurs or the end
       of the file is reached.

FILES
       /etc/services
              services database file

CONFORMING TO
       BSD 4.3

SEE ALSO
       getprotoent(3), getnetent(3), services(5)



BSD                               2001-07-25                     GETSERVENT(3)