Unknown option: "-3" Unix manual page for CURLOPT_KRBLEVEL. (host=minya system=Darwin)
CURLOPT_KRBLEVEL(3)        curl_easy_setopt options        CURLOPT_KRBLEVEL(3)

NAME
       CURLOPT_KRBLEVEL - set FTP kerberos security level

SYNOPSIS
       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_KRBLEVEL, char *level);

DESCRIPTION
       Pass a char * as parameter. Set the kerberos security  level  for  FTP;
       this  also  enables  kerberos  awareness.  This is a string that should
       match one of the following: 'clear', 'safe',  'confidential'  or  'pri-
       vate'.   If the string is set but doesn't match one of these, 'private'
       will be used. Set the string to NULL to disable  kerberos  support  for
       FTP.

       The  application  does not have to keep the string around after setting
       this option.

DEFAULT
       NULL

PROTOCOLS
       FTP

EXAMPLE
       TODO

AVAILABILITY
       This option was known as CURLOPT_KRB4LEVEL up to 7.16.3

RETURN VALUE
       Returns CURLE_OK if the option is  supported,  CURLE_UNKNOWN_OPTION  if
       not, or CURLE_OUT_OF_MEMORY if there was insufficient heap space.

SEE ALSO
       CURLOPT_KRBLEVEL(3), CURLOPT_USE_SSL(3),

libcurl 7.54.0                 December 21, 2016           CURLOPT_KRBLEVEL(3)