ARES\_CANCEL(3) Library Functions Manual ARES\_CANCEL(3) # [NAME](#NAME) ares\_cancel - Cancel a resolve # [SYNOPSIS](#SYNOPSIS) ``` #include void ares_cancel(ares_channel_t *channel) ``` # [DESCRIPTION](#DESCRIPTION) The [**ares\_cancel(3)**](/man/os/c-ares/ares_cancel.3) function cancels all lookups/requests made on the the name service channel identified by *channel*. [**ares\_cancel(3)**](/man/os/c-ares/ares_cancel.3) invokes the callbacks for each pending query on the channel, passing a status of **ARES\_ECANCELLED**. These calls give the callbacks a chance to clean up any state which might have been stored in their arguments. If such a callback invocation adds a new request to the channel, that request will *not* be cancelled by the current invocation of [**ares\_cancel(3)**](/man/os/c-ares/ares_cancel.3). # [REENTRANCY](#REENTRANCY) A callback invoked by [**ares\_cancel**(3)](/man/os/c-ares/ares_cancel.3) may call c-ares functions on the same channel. The channel lock is recursive, and each query is unlinked from the library's internal structures before its callback runs, so a reentrant call cannot encounter a query that is part-way through being torn down. This includes starting new lookups, as described above, and reconfiguring the server list with [**ares\_set\_servers\_csv**(3)](/man/os/c-ares/ares_set_servers_csv.3) and related functions. # [AVAILABILITY](#AVAILABILITY) The reentrancy guarantee described above applies as of c-ares version 1.35.0, and c-ares version 1.34.9 on the 1.34 branch. # [SEE ALSO](#SEE_ALSO) [**ares\_init**(3)](/man/os/c-ares/ares_init.3) [**ares\_destroy**(3)](/man/os/c-ares/ares_destroy.3) # [NOTES](#NOTES) This function was added in c-ares 1.2.0 c-ares 1.6.0 and earlier pass a status of **ARES\_ETIMEOUT** instead of **ARES\_ECANCELLED**. 31 March 2004 --- Document: ares_cancel(3) from c-ares 1.34.9-r0 (Chainguard OS) Source: https://github.com/c-ares/c-ares