NAME

       ping_setopt - Set options for a liboping object

SYNOPSIS

         #include <oping.h>

         int ping_setopt (pingobj_t *obj, int opt, void *val);

DESCRIPTION

       The ping_setopt method sets options that apply to all hosts associated with the object obj
       and hosts that are yet to be added to the object.

       The obj argument is a pointer to an liboping object, as returned by ping_construct(3).

       The opt argument specifies the option to set. Use one of the following constants. You can
       check if the required constant is supported by the library at compile time using "#ifdef".
       It is recommended to check for desired features using the "OPING_VERSION" define.

       PING_OPT_TIMEOUT
           The time to wait for a "echo reply" to be received; in seconds. In this case the
           memory pointed to by val is interpreted as a double value and must be greater than
           zero. The default is PING_DEF_TIMEOUT.

       PING_OPT_TTL
           The value written into the time-to-live (= TTL) field of generated ICMP packets. The
           memory pointed to by val is interpreted as an integer. Valid values are 1 through 255.
           Default is PING_DEF_TTL.

       PING_OPT_AF
           The address family to use. The memory pointed to by val is interpreted as an integer
           and must be either AF_UNSPEC, AF_INET, or AF_INET6. This option only affects hosts
           that are being added after this option has been set. Default is PING_DEF_AF. If you
           change this option, and a source address is set (see PING_OPT_SOURCE) that setting
           will be reset.

       PING_OPT_DATA
           Set the data to send. The value passed must be a char-pointer to a null-terminated
           string. By default a 56 byte long string is used so that the packet size of an ICMPv4
           packet is exactly 64 bytes. That's the behavior of the ping(1) command.

       PING_OPT_SOURCE
           Set the source address to use. The value passed must be a char-pointer to a null-
           terminated string specifying either a numerical network address or network hostname.
           This option will ignore the address family setting (as set with PING_OPT_AF) and will
           set the object's address family according to the source address assigned.

       PING_OPT_DEVICE
           Set the outgoing network device to be used. The value passed must be a char-pointer to
           a null-terminated string specifying an interface name (e. g. "eth0"). Please note that
           this might not be supported by all operating systems. In that case, ping_setopt sets
           the error to "operation not supported".

       PING_OPT_QOS
           Sets the Quality of Service flags that should be used when crafting ICMP and ICMPv6
           packets. The memory pointed to by val is interpreted as a "uint8_t".  The byte is
           passed to setsockopt(2) without modification, using the "IP_TOS" (IPv4) or
           "IPV6_TCLASS" (IPv6) option. It is the caller's responsibility to chose a valid bit
           combination. For details, read the ip(7) and ipv6(7) manual pages, as well as
           RFC 2474.

       The val argument is a pointer to the new value. It must not be NULL. It is dereferenced
       depending on the value of the opt argument, see above. The memory pointed to by val is not
       changed.

RETURN VALUE

       ping_setopt returns zero upon success or less than zero upon failure.

SEE ALSO

       ping_construct(3), liboping(3)

AUTHOR

       liboping is written by Florian "octo" Forster <octo at verplant.org>.  Its homepage can be
       found at <http://verplant.org/liboping/>.

       Copyright (c) 2005-2011 by Florian "octo" Forster.