ENDHOSTENT(3P) POSIX Programmer's Manual ENDHOSTENT(3P)
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.
endhostent, gethostent, sethostent - network host database functions
struct hostent *gethostent(void);
void sethostent(int stayopen);
These functions shall retrieve information about hosts. This information is considered to
be stored in a database that can be accessed sequentially or randomly. The implementation
of this database is unspecified.
Note: In many cases this database is implemented by the Domain Name System, as documented
in RFC 1034, RFC 1035, and RFC 1886.
The sethostent() function shall open a connection to the database and set the next entry
for retrieval to the first entry in the database. If the stayopen argument is non-zero,
the connection shall not be closed by a call to gethostent(), gethostbyname(), or gethost-
byaddr(), and the implementation may maintain an open file descriptor.
The gethostent() function shall read the next entry in the database, opening and closing a
connection to the database as necessary.
Entries shall be returned in hostent structures. Refer to gethostbyaddr() for a definition
of the hostent structure.
The endhostent() function shall close the connection to the database, releasing any open
These functions need not be reentrant. A function that is not required to be reentrant is
not required to be thread-safe.
Upon successful completion, the gethostent() function shall return a pointer to a hostent
structure 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.
No errors are defined for endhostent(), gethostent(), and sethostent().
The following sections are informative.
The gethostent() function may return pointers to static data, which may be overwritten by
subsequent calls to any of these functions.
endservent(), gethostbyaddr(), the Base Definitions volume of IEEE Std 1003.1-2001,
Portions of this text are reprinted and reproduced in electronic form from IEEE Std
1003.1, 2003 Edition, Standard for Information Technology -- Portable Operating System
Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 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 orig-
inal Standard can be obtained online at http://www.opengroup.org/unix/online.html .
IEEE/The Open Group 2003 ENDHOSTENT(3P)