CURLECONNECTERROR

CURLECONNECTERROR is an error code associated with the libcurl library, a popular open-source toolkit for transferring data with URLs. This error occurs when libcurl fails to establish a connection to the target server, typically during the initial connection phase of an HTTP, HTTPS, FTP, or other network request.

The error code, defined as CURL_ECONNECT_TOO_MANY_REDIRECTS in some contexts, often indicates issues such as network unreachability, firewall restrictions, DNS resolution failures, or server-side misconfigurations. It may also arise when a proxy server is misconfigured or when the connection is blocked by security measures like intrusion detection systems (IDS) or content filters.

Common causes include incorrect server addresses, timeouts due to slow network responses, or server-side redirects that exceed libcurl’s default limit (usually 20). Developers troubleshooting this error should verify network connectivity, check server availability, and review proxy or firewall settings. Adjusting timeout values or retry mechanisms in the application code may also resolve persistent connection issues.

Libcurl provides detailed error messages via its CURLcode return value, allowing developers to diagnose specific failures. For example, CURL_ECONNREFUSED indicates the server actively rejected the connection, while CURL_EHOSTUNREACH suggests DNS resolution failed. Proper error handling in applications using libcurl ensures graceful degradation when network issues arise.