KNET_HANDLE_ENABLE_PMTUD_NOTIFY(3)

NAME
knet_handle_enable_pmtud_notify - install a callback to receive PMTUd changes

SYNOPSIS
#include <libknet.h>

int knet_handle_enable_pmtud_notify(
    knet_handle_t                                       knet_h,
    void                                               *pmtud_notify_fn_private_data,
    void(*)(void *private_data, unsigned int data_mtu)  pmtud_notify_fn
);

DESCRIPTION

knet_handle_enable_pmtud_notify

knet_h - pointer to knet_handle_t

pmtud_notify_fn_private_data void pointer to data that can be used to identify the callback.

pmtud_notify_fn is a callback function that is invoked every time a path MTU size change is detected. The function allows libknet to notify the user of data MTU, that's the max value that can be send onwire without fragmentation. The data MTU will always be lower than real link MTU because it accounts for protocol overhead, knet packet header and (if configured) crypto overhead, This function MUST NEVER block or add substantial delays.

RETURN VALUE

knet_handle_enable_pmtud_notify returns 0 on success -1 on error and errno is set.

SEE ALSO

knet_handle_remove_datafd(3), knet_handle_get_stats(3), knet_host_add(3), knet_handle_pmtud_setfreq(3), knet_handle_pmtud_get(3), knet_handle_crypto_use_config(3), knet_host_get_id_by_host_name(3), knet_host_get_status(3), knet_link_add_acl(3), knet_link_get_pong_count(3), knet_link_get_priority(3), knet_handle_free(3), knet_handle_enable_sock_notify(3), knet_handle_get_datafd(3), knet_recv(3), knet_link_get_ping_timers(3), knet_log_get_subsystem_id(3), knet_host_remove(3), knet_host_enable_status_change_notify(3), knet_strtoaddr(3), knet_link_rm_acl(3), knet_send(3), knet_handle_get_transport_reconnect_interval(3), knet_link_get_enable(3), knet_link_set_priority(3), knet_log_set_loglevel(3), knet_handle_get_channel(3), knet_link_get_config(3), knet_link_get_link_list(3), knet_get_transport_list(3), knet_get_transport_id_by_name(3), knet_log_get_loglevel_id(3), knet_handle_new_ex(3), knet_host_set_name(3), knet_addrtostr(3), knet_handle_setfwd(3), knet_get_compress_list(3), knet_host_set_policy(3), knet_get_transport_name_by_id(3), knet_handle_enable_filter(3), knet_handle_crypto_rx_clear_traffic(3), knet_handle_compress(3), knet_link_get_status(3), knet_handle_add_datafd(3), knet_send_sync(3), knet_log_get_loglevel_name(3), knet_handle_enable_access_lists(3), knet_host_get_host_list(3), knet_host_get_policy(3), knet_link_set_enable(3), knet_link_set_pong_count(3), knet_log_get_subsystem_name(3), knet_host_get_name_by_host_id(3), knet_link_clear_config(3), knet_log_get_loglevel(3), knet_handle_new(3), knet_handle_pmtud_getfreq(3), knet_handle_pmtud_set(3), knet_handle_clear_stats(3), knet_link_set_config(3), knet_handle_crypto_set_config(3), knet_handle_crypto(3), knet_get_crypto_list(3), knet_handle_set_transport_reconnect_interval(3), knet_link_clear_acl(3), knet_link_set_ping_timers(3), knet_handle_setprio_dscp(3), knet_link_insert_acl(3)

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