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ares_gethostbyname_file(3) [debian man page]

ARES_GETHOSTBYNAME(3)					     Library Functions Manual					     ARES_GETHOSTBYNAME(3)

NAME
ares_gethostbyname_file - Lookup a name in the system's hosts file SYNOPSIS
#include <ares.h> int ares_gethostbyname_file(ares_channel channel, const char *name, int family, struct hostent **host) DESCRIPTION
The ares_gethostbyname_file function performs a host lookup by name against the system's hosts file (or equivalent local hostname data- base). The channel parameter is required, but no asynchronous queries are performed. Instead, the lookup is done via the same mechanism used to perform 'f' lookups (see the lookups options field in ares_init_options(3)). The parameter name gives the hostname as a NUL-termi- nated C string, and family gives the desired type of address for the resulting host entry. The return value indicates whether the query succeeded and, if not, how it failed. It may have any of the following values: ARES_SUCCESS The host lookup completed successfully and host now points to the result (and must be freed with ares_free_hostent(3)). ARES_ENOTFOUND The hostname name was not found. ARES_EFILE There was a file I/O error while performing the lookup. ARES_ENOMEM Memory was exhausted. On successful completion of the query, the pointer pointed to by host points to a struct hostent containing the address of the host returned by the lookup. The user must free the memory pointed to by host when finished with it by calling ares_free_hostent(3). If the lookup did not complete successfully, host will be NULL. AVAILABILITY
Added in c-ares 1.5.4 SEE ALSO
ares_gethostbyname(3), ares_free_hostent(3), ares_init_options(3) AUTHOR
Brad Spencer Copyright 1998 by the Massachusetts Institute of Technology. 25 July 1998 ARES_GETHOSTBYNAME(3)

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ARES_GETNAMEINFO(3)					     Library Functions Manual					       ARES_GETNAMEINFO(3)

NAME
ares_getnameinfo - Address-to-nodename translation in protocol-independent manner SYNOPSIS
#include <ares.h> typedef void (*ares_nameinfo_callback)(void *arg, int status, int timeouts, char *node, char *service) void ares_getnameinfo(ares_channel channel, const struct sockaddr *sa, ares_socklen_t salen, int flags, ares_nameinfo_callback callback, void *arg) DESCRIPTION
The ares_getnameinfo function is defined for protocol-independent address translation. The function is a combination of ares_gethost- byaddr(3) and getservbyport(3). The function will translate the address either by executing a host query on the name service channel iden- tified by channel or it will attempt to resolve it locally if possible. The parameters sa and len give the address as a sockaddr struc- ture, and flags gives the options that the function will use. Valid flags are listed below: ARES_NI_NOFQDN Only the nodename portion of the FQDN is returned for local hosts. ARES_NI_NUMERICHOST The numeric form of the hostname is returned rather than the name. ARES_NI_NAMEREQD An error is returned if the hostname cannot be found in the DNS. ARES_NI_NUMERICSERV The numeric form of the service is returned rather than the name. ARES_NI_TCP The service name is to be looked up for the TCP protocol. ARES_NI_UDP The service name is to be looked up for the UDP protocol. ARES_NI_SCTP The service name is to be looked up for the SCTP protocol. ARES_NI_DCCP The service name is to be looked up for the DCCP protocol. ARES_NI_NUMERICSCOPE The numeric form of the scope ID is returned rather than the name. ARES_NI_LOOKUPHOST A hostname lookup is being requested. ARES_NI_LOOKUPSERVICE A service name lookup is being requested. When the query is complete or has failed, the ares library will invoke callback. Completion or failure of the query may happen immedi- ately, or may happen during a later call to ares_process(3), ares_destroy(3) or ares_cancel(3). The callback argument arg is copied from the ares_getnameinfo argument arg. The callback argument status indicates whether the query suc- ceeded and, if not, how it failed. It may have any of the following values: ARES_SUCCESS The host lookup completed successfully. ARES_ENOTIMP The ares library does not know how to look up addresses of type family. ARES_ENOTFOUND The address addr was not found. ARES_ENOMEM Memory was exhausted. ARES_EDESTRUCTION The name service channel channel is being destroyed; the query will not be completed. ARES_EBADFLAGS The flags parameter contains an illegal value. The callback argument timeouts reports how many times a query timed out during the execution of the given request. On successful completion of the query, the callback argument node contains a string representing the hostname (assuming ARES_NI_LOOKUPHOST was specified). Additionally, service contains a string representing the service name (assuming ARES_NI_LOOKUPSERVICE was specified). If the query did not complete successfully, or one of the values was not requested, node or service will be NULL. SEE ALSO
ares_process(3), ares_getaddrinfo(3) AUTHOR
Dominick Meglio Copyright 2005 by Dominick Meglio. 1 May 2009 ARES_GETNAMEINFO(3)
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