curl_global_init_mem(3) Library Functions Manual curl_global_init_mem(3)
NAME
curl_global_init_mem - global libcurl initialization with memory
callbacks
SYNOPSIS
#include <curl/curl.h>
CURLcode curl_global_init_mem(long flags,
curl_malloc_callback m,
curl_free_callback f,
curl_realloc_callback r,
curl_strdup_callback s,
curl_calloc_callback c);
DESCRIPTION
This function works exactly as curl_global_init(3) with one addition:
it allows the application to set callbacks to replace the otherwise
used internal memory functions.
If you are using libcurl from multiple threads or libcurl was built
with the threaded resolver option then the callback functions must be
thread safe. The threaded resolver is a common build option to enable
(and in some cases the default) so we strongly urge you to make your
callback functions thread safe.
All callback arguments must be set to valid function pointers. The
prototypes for the given callbacks must match these:
void *malloc_callback(size_t size);
To replace malloc()
void free_callback(void *ptr);
To replace free()
void *realloc_callback(void *ptr, size_t size);
To replace realloc()
char *strdup_callback(const char *str);
To replace strdup()
void *calloc_callback(size_t nmemb, size_t size);
To replace calloc()
This function is otherwise the same as curl_global_init(3),
please refer to that man page for documentation.
CAUTION
Manipulating these gives considerable powers to the application to
severely screw things up for libcurl. Take care.
PROTOCOLS
This functionality affects all supported protocols
EXAMPLE
extern void *malloc_cb(size_t);
extern void free_cb(void *);
extern void *realloc_cb(void *, size_t);
extern char *strdup_cb(const char *);
extern void *calloc_cb(size_t, size_t);
int main(void)
{
curl_global_init_mem(CURL_GLOBAL_DEFAULT, malloc_cb,
free_cb, realloc_cb,
strdup_cb, calloc_cb);
}
AVAILABILITY
Added in curl 7.12.0
RETURN VALUE
This function returns a CURLcode indicating success or error.
CURLE_OK (0) means everything was OK, non-zero means an error occurred,
see libcurl-errors(3). If CURLOPT_ERRORBUFFER(3) was set with
curl_easy_setopt(3) there can be an error message stored in the error
buffer when non-zero is returned.
SEE ALSO
curl_global_cleanup(3), curl_global_init(3)
libcurl 2025-02-08 curl_global_init_mem(3)
curl 8.12.0 - Generated Wed Feb 19 13:47:03 CST 2025