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Source Code File 05-03_ftpfile1.c

#include <stdio.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <curl/curl.h>

static size_t read_callback(
    void *ptr,
    size_t size,
    size_t nmemb,
    void *user_data)
{
    FILE *local_fp;
    size_t r;
    
    /* initialize local pointer */
    local_fp = (FILE *)user_data;

    /* read a chunk from the file */
    r = fread(ptr, size, nmemb, local_fp);

    return(r);
}

int main()
{
    char ftp_upload[] = "ftp://127.0.0.0/image1.jpg";
    char user_pass[] = "username:password";
    char upload_filename[] = "image1.jpg";
    CURL *curl;
    CURLcode res;
    FILE *input;
    struct stat finfo;
    int file_size;

    /* get the file size */
    stat(upload_filename, &finfo);
    file_size = finfo.st_size;

    /* open the file */
    input = fopen( upload_filename, "rb");
    if( input==NULL)
    {
        fprintf(stderr,
            "Unable to read from %s\n",
            upload_filename);
        exit(1);
    }

    /* initialize curl */
    curl = curl_easy_init();
    
    puts("Preparing FTP...");
    /* set options for FPT upload */
    curl_easy_setopt(curl,
        CURLOPT_URL, ftp_upload);
    curl_easy_setopt(curl,
        CURLOPT_FOLLOWLOCATION, 1L);
    curl_easy_setopt(curl,
        CURLOPT_USERPWD, user_pass);
    curl_easy_setopt(curl,
        CURLOPT_UPLOAD, 1L);
    curl_easy_setopt(curl,
        CURLOPT_INFILESIZE_LARGE,
        (curl_off_t)file_size);
    curl_easy_setopt(curl,
        CURLOPT_READFUNCTION,
        read_callback);
    curl_easy_setopt(curl,
        CURLOPT_READDATA, input);
    
    /* request-send upload */
    res = curl_easy_perform(curl);
    if( res!=CURLE_OK )
    {
        fprintf(stderr,
            "curl upload failed: %s\n",
            curl_easy_strerror(res));
        fclose(input);
        exit(1);
    }

    /* cleanup */
    curl_easy_cleanup(curl);
    fclose(input);
    /* inform the user */
    puts("FTP upload complete");
    
    return(0);
}

Notes

* The ftp_upload[] string is a placeholder. Replace it with a legitimate FTP server name and filename appended.

* The user_pass[] string is also a placeholder.

* Ensure that the upload_filename[] string references a valid file on the local system.

* Wide version of this code (statements not split)