GETPROTOENT
Section: Linux Programmer's Manual (3)
Updated: 2017-09-15
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NAME
getprotoent, getprotobyname, getprotobynumber, setprotoent,
endprotoent - get protocol entry
SYNOPSIS
#include <netdb.h>
struct protoent *getprotoent(void);
struct protoent *getprotobyname(const char *name);
struct protoent *getprotobynumber(int proto);
void setprotoent(int stayopen);
void endprotoent(void);
DESCRIPTION
The
getprotoent()
function reads the next entry from the protocols database (see
protocols(5))
and returns a
protoent
structure
containing the broken-out fields from the entry.
A connection is opened to the database if necessary.
The
getprotobyname()
function returns a
protoent
structure
for the entry from the database
that matches the protocol name
name.
A connection is opened to the database if necessary.
The
getprotobynumber()
function returns a
protoent
structure
for the entry from the database
that matches the protocol number
number.
A connection is opened to the database if necessary.
The
setprotoent()
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
getproto*()
functions.
The
endprotoent()
function closes the connection to the database.
The
protoent
structure is defined in
<netdb.h>
as follows:
struct protoent {
char *p_name; /* official protocol name */
char **p_aliases; /* alias list */
int p_proto; /* protocol number */
}
The members of the
protoent
structure are:
- p_name
-
The official name of the protocol.
- p_aliases
-
A NULL-terminated list of alternative names for the protocol.
- p_proto
-
The protocol number.
RETURN VALUE
The
getprotoent(),
getprotobyname()
and
getprotobynumber()
functions return a pointer to a
statically allocated
protoent
structure, or a null pointer if an
error occurs or the end of the file is reached.
FILES
- /etc/protocols
-
protocol database file
ATTRIBUTES
For an explanation of the terms used in this section, see
attributes(7).
| Interface | Attribute | Value
|
|
getprotoent()
| Thread safety |
MT-Unsafe race:protoent
race:protoentbuf locale
|
|
getprotobyname()
| Thread safety |
MT-Unsafe race:protobyname
locale
|
|
getprotobynumber()
| Thread safety |
MT-Unsafe race:protobynumber
locale
|
setprotoent(),
endprotoent()
| Thread safety |
MT-Unsafe race:protoent
locale
|
In the above table,
protoent
in
race:protoent
signifies that if any of the functions
setprotoent(),
getprotoent(),
or
endprotoent()
are used in parallel in different threads of a program,
then data races could occur.
CONFORMING TO
POSIX.1-2001, POSIX.1-2008, 4.3BSD.
SEE ALSO
getnetent(3),
getprotoent_r(3),
getservent(3),
protocols(5)
COLOPHON
This page is part of release 4.13 of the Linux
man-pages
project.
A description of the project,
information about reporting bugs,
and the latest version of this page,
can be found at
https://www.kernel.org/doc/man-pages/.
Index
- NAME
-
- SYNOPSIS
-
- DESCRIPTION
-
- RETURN VALUE
-
- FILES
-
- ATTRIBUTES
-
- CONFORMING TO
-
- SEE ALSO
-
- COLOPHON
-
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|
- Running on 
-
:
: 