libcurl http post send data to server

Question

curl_easy_setopt(curl, CURLOPT_URL, "127.0.0.1:8081/get.php");
curl_easy_setopt(curl, CURLOPT_POSTFIELDS,"pulse=70 & temp=35" );

this above code run successfully but when I pass this

int pulsedata = 70;
int tempdata  = 35;

curl_easy_setopt(curl, CURLOPT_POSTFIELDS, "pulse=pulsedata & temp = tempdata");

when I run this above line it give me error how can I pass this pulsedata and tempdata ??

Use a `std::ostream` to build the query URL. – πάντα ῥεῖ Aug 17 '15 at 08:23 — πάντα ῥεῖ, Aug 17 '15 at 08:23

score 0 · Answer 1 · answered Aug 17 '15 at 08:24

You can't use variable in strings like that, you have to format the string.

A possible C++ solution might be to use std::ostringstream like this:

std::ostringstream os;
os << "pulse=" << pulsedata << "&temp=" << tempdata;
curl_easy_setopt(curl, CURLOPT_POSTFIELDS, os.str().c_sr());

With this solution, the std::ostringstream object (os in my example) needs to be alive until the CURL calls are all done.

Also note that the query-string I construct does not contain any spaces.

Jabberwocky · Accepted Answer · 2015-08-17T08:43:40.620

0

A possible C solution:

char sendbuffer[100];
snprintf(sendbuffer, sizeof(sendbuffer), "pulse=%d&temp=%d", pulsedate, tempdata);
curl_easy_setopt(curl, CURLOPT_POSTFIELDS, sendbuffer);

edited Aug 17 '15 at 08:43

answered Aug 17 '15 at 08:33

Jabberwocky

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eclipse give me warning format '%d' expects a matching 'int' argument [-Wformat=] – parth Kanthariya Aug 17 '15 at 08:42
@parth9966 there was an extra `"` in my answer. I edited the answer and now it's correct. Try again. – Jabberwocky Aug 17 '15 at 08:44
i am pass pulsedata=70 but in database enter pulsedata = 1553236 – parth Kanthariya Aug 17 '15 at 08:45
@parth9966 and please show the declaration of `pulsedata` and `tempdata`. – Jabberwocky Aug 17 '15 at 08:45
sorry my mistake your code is working thanks michael – parth Kanthariya Aug 17 '15 at 08:46
one more thing i want to ask you michale in this libcurl http post code run after it logout form the program how can i stop it and run continue ? – parth Kanthariya Aug 17 '15 at 08:56
@parth9966 please ask another question for this. – Jabberwocky Aug 17 '15 at 09:02

libcurl http post send data to server

2 Answers2