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Diffstat (limited to 'man3/getservent.3')
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diff --git a/man3/getservent.3 b/man3/getservent.3 new file mode 100644 index 0000000..fdd5d91 --- /dev/null +++ b/man3/getservent.3 @@ -0,0 +1,209 @@ +'\" t +.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk) +.\" +.\" SPDX-License-Identifier: Linux-man-pages-copyleft +.\" +.\" References consulted: +.\" Linux libc source code +.\" Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991) +.\" 386BSD man pages +.\" Modified Sat Jul 24 19:19:11 1993 by Rik Faith (faith@cs.unc.edu) +.\" Modified Wed Oct 18 20:23:54 1995 by Martin Schulze <joey@infodrom.north.de> +.\" Modified Mon Apr 22 01:50:54 1996 by Martin Schulze <joey@infodrom.north.de> +.\" 2001-07-25 added a clause about NULL proto (Martin Michlmayr or David N. Welton) +.\" +.TH getservent 3 2023-07-20 "Linux man-pages 6.05.01" +.SH NAME +getservent, getservbyname, getservbyport, setservent, endservent \- +get service entry +.SH LIBRARY +Standard C library +.RI ( libc ", " \-lc ) +.SH SYNOPSIS +.nf +.B #include <netdb.h> +.PP +.B struct servent *getservent(void); +.PP +.BI "struct servent *getservbyname(const char *" name ", const char *" proto ); +.BI "struct servent *getservbyport(int " port ", const char *" proto ); +.PP +.BI "void setservent(int " stayopen ); +.B void endservent(void); +.fi +.SH DESCRIPTION +The +.BR getservent () +function reads the next entry from the services database (see +.BR services (5)) +and returns a +.I servent +structure containing +the broken-out fields from the entry. +A connection is opened to the database if necessary. +.PP +The +.BR getservbyname () +function returns a +.I servent +structure +for the entry from the database +that matches the service +.I name +using protocol +.IR proto . +If +.I proto +is NULL, any protocol will be matched. +A connection is opened to the database if necessary. +.PP +The +.BR getservbyport () +function returns a +.I servent +structure +for the entry from the database +that matches the port +.I port +(given in network byte order) +using protocol +.IR proto . +If +.I proto +is NULL, any protocol will be matched. +A connection is opened to the database if necessary. +.PP +The +.BR setservent () +function opens a connection to the database, +and sets the next entry to the first entry. +If +.I stayopen +is nonzero, +then the connection to the database +will not be closed between calls to one of the +.BR getserv* () +functions. +.PP +The +.BR endservent () +function closes the connection to the database. +.PP +The +.I servent +structure is defined in +.I <netdb.h> +as follows: +.PP +.in +4n +.EX +struct servent { + char *s_name; /* official service name */ + char **s_aliases; /* alias list */ + int s_port; /* port number */ + char *s_proto; /* protocol to use */ +} +.EE +.in +.PP +The members of the +.I servent +structure are: +.TP +.I s_name +The official name of the service. +.TP +.I s_aliases +A NULL-terminated list of alternative names for the service. +.TP +.I s_port +The port number for the service given in network byte order. +.TP +.I s_proto +The name of the protocol to use with this service. +.SH RETURN VALUE +The +.BR getservent (), +.BR getservbyname (), +and +.BR getservbyport () +functions return a pointer to a +statically allocated +.I servent +structure, or NULL if an +error occurs or the end of the file is reached. +.SH FILES +.TP +.I /etc/services +services database file +.SH ATTRIBUTES +For an explanation of the terms used in this section, see +.BR attributes (7). +.TS +allbox; +lb lb lbx +l l l. +Interface Attribute Value +T{ +.na +.nh +.BR getservent () +T} Thread safety T{ +.na +.nh +MT-Unsafe race:servent +race:serventbuf locale +T} +T{ +.na +.nh +.BR getservbyname () +T} Thread safety T{ +.na +.nh +MT-Unsafe race:servbyname +locale +T} +T{ +.na +.nh +.BR getservbyport () +T} Thread safety T{ +.na +.nh +MT-Unsafe race:servbyport +locale +T} +T{ +.na +.nh +.BR setservent (), +.BR endservent () +T} Thread safety T{ +.na +.nh +MT-Unsafe race:servent +locale +T} +.TE +.sp 1 +In the above table, +.I servent +in +.I race:servent +signifies that if any of the functions +.BR setservent (), +.BR getservent (), +or +.BR endservent () +are used in parallel in different threads of a program, +then data races could occur. +.SH STANDARDS +POSIX.1-2008. +.SH HISTORY +POSIX.1-2001, 4.3BSD. +.SH SEE ALSO +.BR getnetent (3), +.BR getprotoent (3), +.BR getservent_r (3), +.BR services (5) |