CURLOPT_ALTSVC(3) Library Functions Manual CURLOPT_ALTSVC(3)
NAME
CURLOPT_ALTSVC - alt-svc cache filename
SYNOPSIS
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_ALTSVC, char *filename);
DESCRIPTION
Pass in a pointer to a filename to instruct libcurl to use that file as
the Alt-Svc cache to read existing cache contents from and possibly
also write it back to after a transfer, unless CURLALTSVC_READONLYFILE
is set in CURLOPT_ALTSVC_CTRL(3).
Specify a blank filename ("") to make libcurl not load from a file at
all.
DEFAULT
NULL. The alt-svc cache is not read nor written to file.
PROTOCOLS
This functionality affects http only
EXAMPLE
int main(void)
{
CURL *curl = curl_easy_init();
if(curl) {
curl_easy_setopt(curl, CURLOPT_ALTSVC_CTRL, CURLALTSVC_H1);
curl_easy_setopt(curl, CURLOPT_ALTSVC, "altsvc-cache.txt");
curl_easy_perform(curl);
}
}
FILE FORMAT
A text based file with one line per alt-svc entry and each line
consists of nine space-separated fields.
An example line could look like
h2 www.example.com 8443 h3 second.example.com 443 "20190808 06:18:37" 1 0
The fields of that line are:
h2 ALPN id for the source origin
www.example.comp
Hostname for the source origin
8443 Port number for the source origin
h3 ALPN id for the destination host
second.example.com
Hostname for the destination host
443 Port number for the destination host
2019* Expiration date and time of this entry within double quotes. The
date format is "YYYYMMDD HH:MM:SS" and the time zone is GMT.
1 Boolean (1 or 0) if "persist" was set for this entry
0 Integer priority value (not currently used)
AVAILABILITY
Added in curl 7.64.1
RETURN VALUE
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION
if not.
SEE ALSO
CURLOPT_ALTSVC_CTRL(3), CURLOPT_CONNECT_TO(3), CURLOPT_COOKIEFILE(3),
CURLOPT_RESOLVE(3)
libcurl 2024-08-05 CURLOPT_ALTSVC(3)
curl 8.9.1 - Generated Wed Aug 7 11:43:10 CDT 2024