CURLOPT\_FNMATCH\_FUNCTION(3) Library Functions Manual CURLOPT\_FNMATCH\_FUNCTION(3)

# [NAME](#NAME)

CURLOPT\_FNMATCH\_FUNCTION - wildcard match callback

# [SYNOPSIS](#SYNOPSIS)

```
#include <curl/curl.h>
int fnmatch_callback(void *ptr,


                     const char *pattern,


                     const char *string);
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FNMATCH_FUNCTION,


                          fnmatch_callback);
```

# [DESCRIPTION](#DESCRIPTION)

Pass a pointer to your callback function, which should match the prototype shown above.

This callback is used for wildcard matching.

Return *CURL\_FNMATCHFUNC\_MATCH* if pattern matches the string, *CURL\_FNMATCHFUNC\_NOMATCH* if not or *CURL\_FNMATCHFUNC\_FAIL* if an error occurred.

# [DEFAULT](#DEFAULT)

NULL == an internal function for wildcard matching.

# [PROTOCOLS](#PROTOCOLS)

This functionality affects ftp only

# [EXAMPLE](#EXAMPLE)

```
extern int string_match(const char *s1, const char *s2);
struct local_stuff {


  void *custom;
};
static int my_fnmatch(void *clientp,


                      const char *pattern, const char *string)
{


  struct local_stuff *data = clientp;


  printf("my pointer: %p\n", data->custom);


  if(string_match(pattern, string))


    return CURL_FNMATCHFUNC_MATCH;


  else


    return CURL_FNMATCHFUNC_NOMATCH;
}
int main(void)
{


  struct local_stuff local_data;


  CURL *curl = curl_easy_init();


  if(curl) {


    CURLcode result;


    curl_easy_setopt(curl, CURLOPT_URL, "ftp://ftp.example.com/file*");


    curl_easy_setopt(curl, CURLOPT_WILDCARDMATCH, 1L);


    curl_easy_setopt(curl, CURLOPT_FNMATCH_FUNCTION, my_fnmatch);


    curl_easy_setopt(curl, CURLOPT_FNMATCH_DATA, &local_data);


    result = curl_easy_perform(curl);


    curl_easy_cleanup(curl);


  }
}
```

# [AVAILABILITY](#AVAILABILITY)

Added in curl 7.21.0

# [RETURN VALUE](#RETURN_VALUE)

[*curl\_easy\_setopt(3)*](/man/os/curl/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)*](/man/os/curl/libcurl-errors.3).

# [SEE ALSO](#SEE_ALSO)

[**CURLOPT\_DEBUGFUNCTION**(3)](/man/os/curl/CURLOPT_DEBUGFUNCTION.3), [**CURLOPT\_FNMATCH\_DATA**(3)](/man/os/curl/CURLOPT_FNMATCH_DATA.3), [**CURLOPT\_WILDCARDMATCH**(3)](/man/os/curl/CURLOPT_WILDCARDMATCH.3)

2026-10-31 libcurl

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Document: CURLOPT_FNMATCH_FUNCTION(3) from curl 8.23.0-r3 (Chainguard OS)
Source: https://github.com/curl/curl.git