Computer Science


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

NAME
       getservent, getservbyname, getservbyport, setservent, end-
       servent - 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/services  and  returns a structure servent con-
       taining  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.

       The  getservbyport()  function returns a servent structure
       for the line that matches the port port given  in  network
       byte order using protocol proto.

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

       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                       22 April 1996                         1

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