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 entry from the services database (see services(5)) and returns a servent structure containing the
broken-out fields from the entry. A connection is opened to the database if necessary.
The getservbyname() function returns a servent structure for the entry
from the database that matches the service name using protocol proto.
If proto is NULL, any protocol will be matched. A connection is opened
to the database if necessary.
The getservbyport() function returns a servent structure for the entry
from the database that matches the port port (given in network byte
order) using protocol proto. If proto is NULL, any protocol will be
matched. A connection is opened to the database if necessary.
The setservent() function opens a connection to the database, and sets
the next entry to the first entry. If stayopen is nonzero, then the
connection to the database will not be closed between calls to one of
the getserv*() functions.
The endservent() function closes the connection to the database.
- 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 NULL-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
a pointer to a statically allocated 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
4.3BSD, POSIX.1-2001.
SEE ALSO
getnetent(3), getprotoent(3), getservent_r(3), services(5)
COLOPHON
- This page is part of release 3.25 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.