moparisthebest/curl
1
0
Fork 0
mirror of https://github.com/moparisthebest/curl synced 2024-11-12 12:35:04 -05:00
Code Issues Releases Wiki Activity

curl_multi_fdset: clarify the max_fd == -1 case

Browse Source 
Elaborate what max_fd == -1 means

Remove the reference to CURLM_CALL_MULTI_PERFORM as modern libcurl
versions don't ever return that.
This commit is contained in:
Daniel Stenberg 2011-10-16 23:38:48 +02:00
parent 840eff44f2
commit 337252bdd4
1 changed files with 7 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
docs/libcurl/curl_multi_fdset.3
View File

@ -40,14 +40,15 @@ but be sure to FD_ZERO them before calling this function as
otherwise remove any others. The \fIcurl_multi_perform(3)\fP function should be
called as soon as one of them is ready to be read from or written to.
To be sure to have up-to-date results, you should call
\fIcurl_multi_perform\fP until it does not return CURLM_CALL_MULTI_PERFORM
prior to calling \fIcurl_multi_fdset\fP. This will make sure that libcurl has
updated the handles' socket states.
If no file descriptors are set by libcurl, \fImax_fd\fP will contain -1 when
this function returns. Otherwise it will contain the higher descriptor number
libcurl set.
libcurl set. When libcurl returns -1 in \fImax_fd\fP, it is because libcurl
currently does something that isn't possible for your application to monitor
with a socket and unfortunately you can then not know exactly when the current
action is completed using select(). When max_fd returns with -1, you need to
wait a while and then proceed and call \fIcurl_multi_perform\fP anyway. How
long to wait? I would suggest 100 milliseconds at least, but you may want to
test it out in your own particular conditions to find a suitable value.
When doing select(), you should use \fBcurl_multi_timeout\fP to figure out how
long to wait for action. Call \fIcurl_multi_perform\fP even if no activity has