CURLOPT_UPLOAD_FLAGS(3) Library Functions Manual CURLOPT_UPLOAD_FLAGS(3)
NAME
CURLOPT_UPLOAD_FLAGS - upload flags for IMAP
SYNOPSIS
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_UPLOAD_FLAGS, long bitmask);
DESCRIPTION
Pass a long as parameter, which is set to a bitmask, to tell libcurl
which flags to send the server relating to uploaded files. The current
supported flags are CURLULFLAG_ANSWERED, which sets the Answered flag
for IMAP uploads, CURLULFLAG_DELETED, which sets the Deleted flag for
IMAP uploads, CURLULFLAG_DRAFT, which sets the Draft flag for IMAP up-
loads, CURLULFLAG_FLAGGED, which sets the Flagged flag for IMAP uploads,
and CURLULFLAG_SEEN, which sets the Seen flag for IMAP uploads.
DEFAULT
A bitmask with only the CURLULFLAG_SEEN flag set.
PROTOCOLS
This functionality affects imap and imaps
EXAMPLE
static size_t read_cb(char *ptr, size_t size, size_t nmemb, void *userdata)
{
FILE *src = userdata;
/* copy as much data as possible into the 'ptr' buffer, but no more than
'size' * 'nmemb' bytes */
size_t retcode = fread(ptr, size, nmemb, src);
return retcode;
}
int main(void)
{
CURL *curl = curl_easy_init();
if(curl) {
FILE *src = fopen("local-file", "r");
curl_off_t fsize = 9876; /* set this to the size of the input file */
/* we want to use our own read function */
curl_easy_setopt(curl, CURLOPT_READFUNCTION, read_cb);
/* enable uploading */
curl_easy_setopt(curl, CURLOPT_UPLOAD, 1L);
/* specify target */
curl_easy_setopt(curl, CURLOPT_URL, "imap://example.com:993/mailbox");
/* provide username */
curl_easy_setopt(curl, CURLOPT_USERNAME, "user@example.com");
/* provide password */
curl_easy_setopt(curl, CURLOPT_PASSWORD, "password");
/* specify that uploaded mail should be considered flagged */
curl_easy_setopt(curl, CURLOPT_UPLOAD_FLAGS, CURLULFLAG_FLAGGED);
/* now specify which pointer to pass to our callback */
curl_easy_setopt(curl, CURLOPT_READDATA, src);
/* Set the size of the file to upload */
curl_easy_setopt(curl, CURLOPT_INFILESIZE_LARGE, (curl_off_t)fsize);
/* perform the upload */
curl_easy_perform(curl);
}
}
AVAILABILITY
Added in curl 8.13.0
RETURN VALUE
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).
SEE ALSO
CURLOPT_UPLOAD(3)
libcurl 2026-07-12 CURLOPT_UPLOAD_FLAGS(3)
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