A simple C app that creates PDF from a local HTML file

pdfcrowd.c

/* compile with: $ gcc pdfcrowd.c -lcurl -o pdfcrowd */
#include <curl/curl.h>

/*
 *  return values:
 *    0    success
 *    1    curl fatal error
 *    2    curl error
 *   >399  API error (HTTP status code)
 */
long file_to_pdf(char const* fname, FILE* outfp,
                 char const* username, char const* apikey) {

    long status_code = 0;
    CURLcode res;
    struct curl_httppost* post = NULL;
    struct curl_httppost* last = NULL;
    char errbuffer[1024];
    int eread = 0;

    CURL *curl = curl_easy_init();
    if (!curl) {
        fprintf(stderr, "curl_easy_init() failed\n");
        return 1;
    }

    curl_formadd(&post,
                 &last,
                 CURLFORM_COPYNAME,"username",
                 CURLFORM_COPYCONTENTS, username,
                 CURLFORM_END);

    curl_formadd(&post,
                 &last,
                 CURLFORM_COPYNAME,"key",
                 CURLFORM_COPYCONTENTS, apikey,
                 CURLFORM_END);

    curl_formadd(&post,
                 &last,
                 CURLFORM_COPYNAME, "src",
                 CURLFORM_FILECONTENT, fname,
                 CURLFORM_END);


    curl_easy_setopt(curl, CURLOPT_URL, "http://pdfcrowd.com/api/pdf/convert/html/");
    curl_easy_setopt(curl, CURLOPT_HTTPPOST, post);
    curl_easy_setopt(curl, CURLOPT_WRITEDATA, outfp);

    res = curl_easy_perform(curl);
    curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &status_code);
    if (res != CURLE_OK) {
        fprintf(stderr, "curl_easy_perform() failed: %s\n",
                curl_easy_strerror(res));
        status_code = 2;
    } else if (status_code >= 400) {
        /* assumes outfp is seekable */
        fseek(outfp, 0, SEEK_SET);
        fprintf(stderr, "Pdfcrowd Error: [%d] ", status_code);
        do {
            eread = fread(errbuffer, 1, 1024, outfp);
            fwrite(errbuffer, 1, eread, stderr);
        } while (eread);
    } else {
        /* success */
        status_code = 0;
    }

cleanup:
    curl_formfree(post);
    curl_easy_cleanup(curl);
    return status_code;
}


int main(char argc, char **argv) {

    long status;
    char const* output_fname = "out.pdf";
    FILE* outfp = fopen(output_fname, "w+b");

    status = file_to_pdf("sample.html", outfp, "**username**", "**apikey**");
    fclose(outfp);

    if (status) {
        remove(output_fname);
        return 1;
    }

    return 0;
}