:man| Alphabetical   Categories   About us 
 
REALHOSTNAME_SA (3) | C library functions | Unix Manual Pages | :man

NAME

realhostname_sa - "convert a"
.Vt "struct sockaddr" to the real host name

CONTENTS

Library
Synopsis
Description
Return Values
See Also

LIBRARY


.Lb libutil

SYNOPSIS


.In sys/types.h
.In netinet/in.h
.In libutil.h int realhostname_sa "char *host" "size_t hsize" "struct sockaddr *addr" "int addrlen"

DESCRIPTION

The function realhostname_sa converts addr to the corresponding host name. This is done by resolving addr to a host name and then ensuring that the host name resolves back to addr.

host must point to a buffer of at least hsize bytes, and will always be written to by this function.

If the name resolution does not work both ways or if the host name is longer than hsize bytes, getnameinfo(3) with NI_NUMERICHOST specified, is used to convert addr to an ASCII form.

If the string written to host is hsize bytes long, host will not be NUL terminated.

RETURN VALUES

The realhostname_sa function will return one of the following constants which are defined in
.In libutil.h :

HOSTNAME_FOUND
A valid host name was found.
HOSTNAME_INCORRECTNAME
A host name was found, but it did not resolve back to the passed ip. host now contains the numeric value of ip.
HOSTNAME_INVALIDADDR
ip could not be resolved. host now contains the numeric value of ip.
HOSTNAME_INVALIDNAME
A host name was found, but it could not be resolved back to any ip number. host now contains the numeric value of ip.

SEE ALSO

getaddrinfo(3), getnameinfo(3), realhostname(3)


Share this page

     Follow us

Facebook Twitter Google+ LinkedIn


 
Created by Blin Media, 2008-2013