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+--- Thread: How do I properly use curl inside a C program? or Having trouble with curl inside a C program—any tip (/thread-how-do-i-properly-use-curl-inside-a-c-program-or-having-trouble-with-curl-inside-a-c-program%E2%80%94any-tip)
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How do I properly use curl inside a C program? or Having trouble with curl inside a C program—any tip - fastXpert99 - 20-02-2025
"Having trouble with curl inside a c program—any tips?"
Hey folks,
So I'm trying to use curl inside a c program, and it's driving me nuts. I followed some tutorials, but my requests keep failing or just... don't work?
Like, I set up the easy handle, added the URL, but the response is either garbage or nothing. Am I missing something obvious?
Also, is there a *simple* example out there for curl inside a c program? The official docs are kinda overwhelming, ngl.
Any help or even a dumbed-down snippet would be a lifesaver. Thanks!
---
*PS: If you've got horror stories about curl inside a c program, share 'em. Misery loves company.*
“” - anonyPioneer77 - 09-03-2025
Hey! I've been there—curl inside a c program can be a pain at first. One thing that tripped me up was forgetting to call `curl_global_init()` before anything else.
Also, make sure you're setting the write callback properly if you're trying to capture the response. Here's a barebones example:
```c
#include <curl/curl.h>
int main() {
curl_global_init(CURL_GLOBAL_ALL);
CURL *curl = curl_easy_init();
if(curl) {
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
curl_easy_perform(curl);
curl_easy_cleanup(curl);
}
curl_global_cleanup();
return 0;
}
```
If you're still stuck, check out [this tutorial](https://curl.se/libcurl/c/simple.html). It's way clearer than the official docs.
“” - ghostHawk99 - 27-03-2025
Ugh, I feel your pain. Debugging curl inside a c program is like herding cats sometimes.
Pro tip: Enable verbose mode with `curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L)`. It’ll spit out a ton of info, but at least you’ll see where it’s failing.
Also, double-check your libcurl version. Some older versions have weird quirks.
“” - StealthMind99 - 04-04-2025
Yo! Had the same issue last week. Turns out I wasn’t linking the libcurl library properly.
If you’re using gcc, make sure to add `-lcurl` to your compile command:
```bash
gcc your_program.c -o output -lcurl
```
Also, if you’re on Windows, the linker can be extra fussy. Might wanna check your paths.
“” - InvisibleCircuit99 - 05-04-2025
If you’re getting garbage responses, are you setting a write callback? curl doesn’t store the response by default—you gotta tell it where to put the data.
Here’s a quick write function you can use:
```c
size_t write_callback(char *ptr, size_t size, size_t nmemb, void *userdata) {
printf("%.*s", (int)(size * nmemb), ptr);
return size * nmemb;
}
```
Then set it with `curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_callback)`.
“” - proxyByteX88 - 06-04-2025
Dude, the official examples are *way* overkill for beginners. I found [this repo](https://github.com/bagder/curl) super helpful—it’s got simpler snippets for common tasks.
Also, if you’re on Linux, `strace` can be a lifesaver for seeing what curl’s actually doing under the hood.
“” - fastXpert99 - 07-04-2025
OP here—wow, thanks for all the replies! The verbose flag and write callback were exactly what I needed.
Still getting a weird SSL error though (`CURLE_PEER_FAILED_VERIFICATION`). Anyone know how to bypass that for testing? I’m just playing around locally, so security isn’t a big deal rn.
Also, that typo story hit too close to home lol.
“” - darkTorX - 07-04-2025
Horror story time: Once spent 3 hours debugging curl inside a c program only to realize I’d typo’d the URL. *facepalm*
Anyway, make sure you’re checking error codes! `curl_easy_perform()` returns `CURLE_OK` if it works. If not, `curl_easy_strerror()` will tell you what went wrong.