curl / libcurl / API / curl_easy_setopt / CURLOPT_WILDCARDMATCH

CURLOPT_WILDCARDMATCH explained

Name

CURLOPT_WILDCARDMATCH - directory wildcard transfers

Synopsis

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

Description

Set onoff to 1 if you want to transfer multiple files according to a filename pattern. The pattern can be specified as part of the CURLOPT_URL option, using an fnmatch-like pattern (Shell Pattern Matching) in the last part of URL (filename).

By default, libcurl uses its internal wildcard matching implementation. You can provide your own matching function by the CURLOPT_FNMATCH_FUNCTION option.

A brief introduction of its syntax follows:

* - ASTERISK

ftp://example.com/some/path/*.txt

matches all .txt files in the root directory. Only two asterisks are allowed within the same pattern string.

? - QUESTION MARK

Question mark matches any (exactly one) character.

ftp://example.com/some/path/photo?.jpg

[ - BRACKET EXPRESSION

The left bracket opens a bracket expression. The question mark and asterisk have no special meaning in a bracket expression. Each bracket expression ends by the right bracket and matches exactly one character. Some examples follow:

[a-zA-Z0-9] or [f-gF-G] - character interval

[abc] - character enumeration

[^abc] or [!abc] - negation

[[:name:]] class expression. Supported classes are alnum,lower, space, alpha, digit, print, upper, blank, graph, xdigit.

[][-!^] - special case - matches only '-', ']', '[', '!' or '^'. These characters have no special purpose.

[[]] - escape syntax. Matches '[', ']' or 'e'.

Using the rules above, a filename pattern can be constructed:

ftp://example.com/some/path/[a-z[:upper:]\].jpg

Protocols

This functionality affects ftp only

Example

extern long begin_cb(struct curl_fileinfo *, void *, int);
extern long end_cb(void *ptr);
 
int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    /* turn on wildcard matching */
    curl_easy_setopt(curl, CURLOPT_WILDCARDMATCH, 1L);
 
    /* callback is called before download of concrete file started */
    curl_easy_setopt(curl, CURLOPT_CHUNK_BGN_FUNCTION, begin_cb);
 
    /* callback is called after data from the file have been transferred */
    curl_easy_setopt(curl, CURLOPT_CHUNK_END_FUNCTION, end_cb);
 
    /* See more on https://curl.se/libcurl/c/ftp-wildcard.html */
  }
}

Availability

Added in curl 7.21.0

Return value

Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.