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   getprotobynumber    ( 3 )

получить запись протокола (get protocol entry)

Имя (Name)

getprotoent, getprotobyname, getprotobynumber, setprotoent,
       endprotoent - get protocol entry

Синопсис (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);


Описание (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.


Возвращаемое значение (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.

Файлы (Files)

/etc/protocols
              protocol database file

Атрибуты (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(), │ Thread safety │ MT-Unsafe race:protoent │ │endprotoent() │ │ 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.


Стандарты (Conforming to)

POSIX.1-2001, POSIX.1-2008, 4.3BSD.

Смотри также (See also)

getnetent(3), getprotoent_r(3), getservent(3), protocols(5)