CURLOPT_LOW_SPEED_LIMIT - low speed limit in bytes per second

Added in curl 7.1

0, disabled

Pass a long as parameter. It contains the average transfer speed in bytes per second that the transfer should be below during CURLOPT_LOW_SPEED_TIME(3) seconds for libcurl to consider it to be too slow and abort.

int main(void) { CURL *curl = curl_easy_init(); if(curl) { CURLcode res; curl_easy_setopt(curl, CURLOPT_URL, "https://example.com"); /* abort if slower than 30 bytes/sec during 60 seconds */ curl_easy_setopt(curl, CURLOPT_LOW_SPEED_TIME, 60L); curl_easy_setopt(curl, CURLOPT_LOW_SPEED_LIMIT, 30L); res = curl_easy_perform(curl); if(CURLE_OPERATION_TIMEDOUT == res) { printf("Timeout.\n"); } /* always cleanup */ curl_easy_cleanup(curl); } }

CURLOPT_LOW_SPEED_LIMIT - low speed limit in bytes per second

This functionality affects all supported protocols

curl_easy_setopt(3) returns a CURLcode indicating success or error. CURLE_OK (0) means everything was OK, non-zero means an error occurred, see libcurl-errors(3).

CURLOPT_LOW_SPEED_TIME(3), CURLOPT_MAX_RECV_SPEED_LARGE(3), CURLOPT_MAX_SEND_SPEED_LARGE(3), CURLOPT_TIMEOUT(3) libcurl 2025-06-16 CURLOPT_LOW_SPEED_LIMIT(3)

#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_LOW_SPEED_LIMIT, long speedlimit);