NAME

       ping_iterator_get_info - Receive information about a host

SYNOPSIS

         #include <oping.h>

         int ping_iterator_get_info (pingobj_iter_t *iter,
                         int info,
                         void *buffer,
                         size_t *buffer_len);

DESCRIPTION

       The ping_iterator_get_info method can be used on an host iterator to return various
       information about the current host.

       The iter argument is an iterator as returned by ping_iterator_get(3) or
       ping_iterator_next(3).

       The info argument specifies the type of information returned. Use the following defines:

       PING_INFO_USERNAME
           Return the hostname of the host the iterator points to as supplied by the user.  This
           is the name you passed to ping_host_add(3) and which you need to pass to
           "ping_host_remove", too.

       PING_INFO_HOSTNAME
           Return the hostname of the host the iterator points to. Since the name is looked up
           using the socket address this may differ from the hostname passed to ping_host_add(3).
           The hostname is actually looked up every time you call this method, no cache is
           involved within liboping.

           It is recommended to include "netdb.h" and allocate NI_MAXHOST bytes of buffer.

       PING_INFO_ADDRESS
           Return the address used in ASCII (i.e. human readable) format. The address is looked
           up every time you call this method. 40 bytes should be sufficient for the buffer (16
           octets in hex format, seven colons and one null byte), but more won't hurt.

       PING_INFO_FAMILY
           Returns the address family of the host. The buffer should be big enough to hold an
           integer. The value is either AF_INET or AF_INET6.

       PING_INFO_LATENCY
           Return the last measured latency or less than zero if the timeout occurred before a
           echo response was received. The buffer should be big enough to hold a double value.

       PING_INFO_DROPPED
           Return the number of times that no response was received within the timeout.  This
           value is only increased but may wrap around at the 32 bit boundary.  The buffer should
           be big enough to hold a 32 bit integer, e. g. an "uint32_t".

       PING_INFO_SEQUENCE
           Return the last sequence number sent. This number is increased regardless of echo
           responses being received or not. The buffer should hold an integer.

       PING_INFO_IDENT
           Return the ident that is put into every ICMP packet sent to this host. Per convention
           this usually is the PID of the sending process, but since liboping can handle several
           hosts in parallel it uses a (pseudo-)random number here. The buffer should be big
           enough to hold an integer value.

       PING_INFO_RECV_TTL
           Returns the time to live (TTL) of the received network packets. This number depends on
           the value that was used by the remote host when it sent the echo reply and has nothing
           to do with the PING_OPT_TTL of ping_setopt(3). The buffer should be big enough to hold
           an integer value.

       PING_INFO_RECV_QOS
           Returns the value of the Quality of Service (QoS) byte of the incoming IPv4 or IPv6
           packet. This byte is not interpreted by liboping at all and may be DSCP / ECN or
           precedence / ToS depending on your network setup.  Please see the appropriate RFCs for
           further information on values you can expect to receive. The buffer is expected to an
           "uint8_t".

       The buffer argument is a pointer to an appropriately sized area of memory where the result
       of the call will be stored. The buffer_len value is used as input and output: When calling
       ping_iterator_get_info it reports the size of the memory region pointed to by buffer. The
       method will write the number of bytes actually written to the memory into buffer_len
       before returning.

RETURN VALUE

       ping_iterator_get_info returns zero if it succeeds.

       EINVAL is returned if the value passed as info is unknown. Both, buffer and buffer_len,
       will be left untouched in this case.

       If the requested information didn't fit into buffer then the size that would have been
       needed is written into buffer_len; buffer itself is left untouched. The return value is
       ENOMEM in this case.

SEE ALSO

       ping_iterator_get(3), liboping(3)

AUTHOR

       liboping is written by Florian "octo" Forster <ff at octo.it>.  Its homepage can be found
       at <http://noping.cc/>.

       Copyright (c) 2006-2017 by Florian "octo" Forster.