| lh | 9ed821d | 2023-04-07 01:36:19 -0700 | [diff] [blame] | 1 | .\" |
| 2 | .\" Copyright 1998 by Daniel Stenberg |
| 3 | .\" |
| 4 | .\" Permission to use, copy, modify, and distribute this |
| 5 | .\" software and its documentation for any purpose and without |
| 6 | .\" fee is hereby granted, provided that the above copyright |
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| 11 | .\" software without specific, written prior permission. |
| 12 | .\" M.I.T. makes no representations about the suitability of |
| 13 | .\" this software for any purpose. It is provided "as is" |
| 14 | .\" without express or implied warranty. |
| 15 | .\" |
| 16 | .TH ARES_GETSOCK 3 "11 March 2010" |
| 17 | .SH NAME |
| 18 | ares_getsock \- get socket descriptors to wait on |
| 19 | .SH SYNOPSIS |
| 20 | .nf |
| 21 | .B #include <ares.h> |
| 22 | .PP |
| 23 | .B int ares_getsock(ares_channel \fIchannel\fP, ares_socket_t *\fIsocks\fP, |
| 24 | .B int \fInumsocks\fP); |
| 25 | .fi |
| 26 | .SH DESCRIPTION |
| 27 | The |
| 28 | .B ares_getsock |
| 29 | function retrieves the set of socket descriptors which the calling |
| 30 | application should wait on for reading and/or writing for the |
| 31 | processing of name service queries pending on the name service channel |
| 32 | identified by |
| 33 | .IR channel . |
| 34 | Socket descriptors will be set in the socket descriptor array pointed to by |
| 35 | \fIsocks\fP. |
| 36 | \fInumsocks\fP is the size of the given array in number of ints. |
| 37 | |
| 38 | This function can only return information about up to 16 sockets. If more are |
| 39 | in use (however unlikely that is), they are simply not reported back. |
| 40 | .SH RETURN VALUES |
| 41 | \fBares_getsock\fP returns a bitmask for what actions to wait for on the |
| 42 | different sockets. The ares.h header file provides these convenience macros to |
| 43 | extract the information appropriately: |
| 44 | |
| 45 | .nf |
| 46 | #define ARES_GETSOCK_MAXNUM 16 /* ares_getsock() can return info about |
| 47 | this many sockets */ |
| 48 | #define ARES_GETSOCK_READABLE(bits,num) (bits & (1<< (num))) |
| 49 | #define ARES_GETSOCK_WRITABLE(bits,num) (bits & (1 << ((num) + \ |
| 50 | ARES_GETSOCK_MAXNUM))) |
| 51 | .fi |
| 52 | .SH NOTES |
| 53 | This function was added in c-ares 1.3.1 |
| 54 | .SH SEE ALSO |
| 55 | .BR ares_timeout (3), |
| 56 | .BR ares_fds (3), |
| 57 | .BR ares_process (3) |