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endprotoent(3p) — Linux manual page

ENDPROTOENT(3P)         POSIX Programmer's ManualENDPROTOENT(3P)

PROLOG        top

       This manual page is part of the POSIX Programmer's Manual.  The       Linux implementation of this interface may differ (consult the       corresponding Linux manual page for details of Linux behavior), or       the interface may not be implemented on Linux.

NAME        top

       endprotoent, getprotobyname, getprotobynumber, getprotoent,       setprotoent — network protocol database functions

SYNOPSIS        top

       #include <netdb.h>       void endprotoent(void);       struct protoent *getprotobyname(const char *name);       struct protoent *getprotobynumber(intproto);       struct protoent *getprotoent(void);       void setprotoent(intstayopen);

DESCRIPTION        top

       These functions shall retrieve information about protocols. This       information is considered to be stored in a database that can be       accessed sequentially or randomly. The implementation of this       database is unspecified.       Thesetprotoent() function shall open a connection to the       database, and set the next entry to the first entry. If thestayopen argument is non-zero, the connection to the network       protocol database shall not be closed after each call togetprotoent() (either directly, or indirectly through one of the       othergetproto*() functions), and the implementation may maintain       an open file descriptor for the database.       Thegetprotobyname() function shall search the database from the       beginning and find the first entry for which the protocol name       specified byname matches thep_name member, opening and closing a       connection to the database as necessary.       Thegetprotobynumber() function shall search the database from the       beginning and find the first entry for which the protocol number       specified byproto matches thep_proto member, opening and closing       a connection to the database as necessary.       Thegetprotoent() function shall read the next entry of the       database, opening and closing a connection to the database as       necessary.       Thegetprotobyname(),getprotobynumber(), andgetprotoent()       functions shall each return a pointer to aprotoentstructure, the       members of which shall contain the fields of an entry in the       network protocol database.       Theendprotoent() function shall close the connection to the       database, releasing any open file descriptor.       These functions need not be thread-safe.

RETURN VALUE        top

       Upon successful completion,getprotobyname(),getprotobynumber(),       andgetprotoent() return a pointer to aprotoentstructure if the       requested entry was found, and a null pointer if the end of the       database was reached or the requested entry was not found.       Otherwise, a null pointer is returned.       The application shall not modify the structure to which the return       value points, nor any storage areas pointed to by pointers within       the structure. The returned pointer, and pointers within the       structure, might be invalidated or the structure or the storage       areas might be overwritten by a subsequent call togetprotobyname(),getprotobynumber(), orgetprotoent().  The       returned pointer, and pointers within the structure, might also be       invalidated if the calling thread is terminated.

ERRORS        top

       No errors are defined.The following sections are informative.

EXAMPLES        top

       None.

APPLICATION USAGE        top

       None.

RATIONALE        top

       None.

FUTURE DIRECTIONS        top

       None.

SEE ALSO        top

       The Base Definitions volume of POSIX.1‐2017,netdb.h(0p)

COPYRIGHT        top

       Portions of this text are reprinted and reproduced in electronic       form from IEEE Std 1003.1-2017, Standard for Information       Technology -- Portable Operating System Interface (POSIX), The       Open Group Base Specifications Issue 7, 2018 Edition, Copyright       (C) 2018 by the Institute of Electrical and Electronics Engineers,       Inc and The Open Group.  In the event of any discrepancy between       this version and the original IEEE and The Open Group Standard,       the original IEEE and The Open Group Standard is the referee       document. The original Standard can be obtained online athttp://www.opengroup.org/unix/online.html .       Any typographical or formatting errors that appear in this page       are most likely to have been introduced during the conversion of       the source files to man page format. To report such errors, seehttps://www.kernel.org/doc/man-pages/reporting_bugs.html .IEEE/The Open Group                2017ENDPROTOENT(3P)

Pages that refer to this page:netdb.h(0p), endservent(3p), getprotobyname(3p), getsockopt(3p), setprotoent(3p), setsockopt(3p)

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