What does curl_multi_getcontent($ch) return if $ch isn't ready?
What does curl_multi_getcontent($ch) return if $ch isn'开发者_高级运维t ready in PHP?
The answer to the question you asked is
- If the response has not been received yet,
curl_multi_getcontent
returnsNULL
. - If the transfer is in progress,
curl_multi_getcontent
returns the data retrieved so far.
The question you meant to ask, apparently, is this: How do I know when a curl_multi...
operation is finished?
The answer is that you don't use curl_multi_getcontent
for this. Instead, repeatedly call curl_multi_exec
until the second parameter (which is the number of sub-handles still working on its transfer) goes to 0. This blog post, from the comments in the manual, shows some working code. You may also want to look at curl_multi_select
, which will block until there's some activity on a connection. This probably leads to fewer cycles wasted making curl_multi_exec
calls: See example #1 on the manual page for curl_multi_exec
.
If you're using version 5.2.0 or later, you can use curl_multi_info_read
to get the status of individual connections instead of waiting for all of them. (manual)
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