curl_unescape - URL decode a string

Added in curl 7.1

Since 7.15.4, curl_easy_unescape(3) should be used. This function might be removed in a future release.

Deprecated. Use curl_easy_unescape(3) instead. This function converts the URL encoded string input to a "plain string" and return that as a new allocated string. All input characters that are URL encoded (%XX where XX is a two-digit hexadecimal number) are converted to their plain text versions. If the length argument is set to 0, curl_unescape(3) calls strlen() on input to find out the size. You must curl_free(3) the returned string when you are done with it.

int main(void) { CURL *curl = curl_easy_init(); if(curl) { char *decoded = curl_unescape("%63%75%72%6c", 12); if(decoded) { /* do not assume printf() works on the decoded data */ printf("Decoded: "); /* ... */ curl_free(decoded); } } }

curl_unescape - URL decode a string

This functionality affects all supported protocols

A pointer to a null-terminated string or NULL if it failed.

RFC2396, curl_easy_escape(3), curl_easy_unescape(3), curl_free(3) libcurl 2025-06-16 curl_unescape(3)

#include <curl/curl.h> char *curl_unescape(const char *input, int length);