CURLcode的定义

经常性遇到libcurl的问题，而且都特别奇怪，记录一下CURLcode的定义：

http://curl.haxx.se/libcurl/c/libcurl-errors.html

#include <curl/curl.h>

enum CURLcode{    CURLE_OK = 0,    CURLE_UNSUPPORTED_PROTOCOL, /* 1 */    CURLE_FAILED_INIT, /* 2 */    CURLE_URL_MALFORMAT, /* 3 */    CURLE_OBSOLETE4, /* 4 - NOT USED */    CURLE_COULDNT_RESOLVE_PROXY, /* 5 */    CURLE_COULDNT_RESOLVE_HOST, /* 6 */    CURLE_COULDNT_CONNECT, /* 7 */    CURLE_FTP_WEIRD_SERVER_REPLY, /* 8 */    CURLE_REMOTE_ACCESS_DENIED, /* 9 a service was denied by the server                                        due to lack of access - when login fails                                        this is not returned. */    CURLE_OBSOLETE10, /* 10 - NOT USED */    CURLE_FTP_WEIRD_PASS_REPLY, /* 11 */    CURLE_OBSOLETE12, /* 12 - NOT USED */    CURLE_FTP_WEIRD_PASV_REPLY, /* 13 */    CURLE_FTP_WEIRD_227_FORMAT, /* 14 */    CURLE_FTP_CANT_GET_HOST, /* 15 */    CURLE_OBSOLETE16, /* 16 - NOT USED */    CURLE_FTP_COULDNT_SET_TYPE, /* 17 */    CURLE_PARTIAL_FILE, /* 18 */    CURLE_FTP_COULDNT_RETR_FILE, /* 19 */    CURLE_OBSOLETE20, /* 20 - NOT USED */    CURLE_QUOTE_ERROR, /* 21 - quote command failure */    CURLE_HTTP_RETURNED_ERROR, /* 22 */    CURLE_WRITE_ERROR, /* 23 */    CURLE_OBSOLETE24, /* 24 - NOT USED */    CURLE_UPLOAD_FAILED, /* 25 - failed upload "command" */    CURLE_READ_ERROR, /* 26 - couldn‘t open/read from file */    CURLE_OUT_OF_MEMORY, /* 27 */    /* Note: CURLE_OUT_OF_MEMORY may sometimes indicate a conversion error               instead of a memory allocation error if CURL_DOES_CONVERSIONS               is defined      */    CURLE_OPERATION_TIMEDOUT, /* 28 - the timeout time was reached */    CURLE_OBSOLETE29, /* 29 - NOT USED */    CURLE_FTP_PORT_FAILED, /* 30 - FTP PORT operation failed */    CURLE_FTP_COULDNT_USE_REST, /* 31 - the REST command failed */    CURLE_OBSOLETE32, /* 32 - NOT USED */    CURLE_RANGE_ERROR, /* 33 - RANGE "command" didn‘t work */    CURLE_HTTP_POST_ERROR, /* 34 */    CURLE_SSL_CONNECT_ERROR, /* 35 - wrong when connecting with SSL */    CURLE_BAD_DOWNLOAD_RESUME, /* 36 - couldn‘t resume download */    CURLE_FILE_COULDNT_READ_FILE, /* 37 */    CURLE_LDAP_CANNOT_BIND, /* 38 */    CURLE_LDAP_SEARCH_FAILED, /* 39 */    CURLE_OBSOLETE40, /* 40 - NOT USED */    CURLE_FUNCTION_NOT_FOUND, /* 41 */    CURLE_ABORTED_BY_CALLBACK, /* 42 */    CURLE_BAD_FUNCTION_ARGUMENT, /* 43 */    CURLE_OBSOLETE44, /* 44 - NOT USED */    CURLE_INTERFACE_FAILED, /* 45 - CURLOPT_INTERFACE failed */    CURLE_OBSOLETE46, /* 46 - NOT USED */    CURLE_TOO_MANY_REDIRECTS, /* 47 - catch endless re-direct loops */    CURLE_UNKNOWN_TELNET_OPTION, /* 48 - User specified an unknown option */    CURLE_TELNET_OPTION_SYNTAX, /* 49 - Malformed telnet option */    CURLE_OBSOLETE50, /* 50 - NOT USED */    CURLE_PEER_FAILED_VERIFICATION, /* 51 - peer‘s certificate or fingerprint                                         wasn‘t verified fine */    CURLE_GOT_NOTHING, /* 52 - when this is a specific error */    CURLE_SSL_ENGINE_NOTFOUND, /* 53 - SSL crypto engine not found */    CURLE_SSL_ENGINE_SETFAILED, /* 54 - can not set SSL crypto engine as                                        default */    CURLE_SEND_ERROR, /* 55 - failed sending network data */    CURLE_RECV_ERROR, /* 56 - failure in receiving network data */    CURLE_OBSOLETE57, /* 57 - NOT IN USE */    CURLE_SSL_CERTPROBLEM, /* 58 - problem with the local certificate */    CURLE_SSL_CIPHER, /* 59 - couldn‘t use specified cipher */    CURLE_SSL_CACERT, /* 60 - problem with the CA cert (path?) */    CURLE_BAD_CONTENT_ENCODING, /* 61 - Unrecognized transfer encoding */    CURLE_LDAP_INVALID_URL, /* 62 - Invalid LDAP URL */    CURLE_FILESIZE_EXCEEDED, /* 63 - Maximum file size exceeded */    CURLE_USE_SSL_FAILED, /* 64 - Requested FTP SSL level failed */    CURLE_SEND_FAIL_REWIND, /* 65 - Sending the data requires a rewind                                        that failed */    CURLE_SSL_ENGINE_INITFAILED, /* 66 - failed to initialise ENGINE */    CURLE_LOGIN_DENIED, /* 67 - user, password or similar was not                                        accepted and we failed to login */    CURLE_TFTP_NOTFOUND, /* 68 - file not found on server */    CURLE_TFTP_PERM, /* 69 - permission problem on server */    CURLE_REMOTE_DISK_FULL, /* 70 - out of disk space on server */    CURLE_TFTP_ILLEGAL, /* 71 - Illegal TFTP operation */    CURLE_TFTP_UNKNOWNID, /* 72 - Unknown transfer ID */    CURLE_REMOTE_FILE_EXISTS, /* 73 - File already exists */    CURLE_TFTP_NOSUCHUSER, /* 74 - No such user */    CURLE_CONV_FAILED, /* 75 - conversion failed */    CURLE_CONV_REQD, /* 76 - caller must register conversion                                        callbacks using curl_easy_setopt options                                        CURLOPT_CONV_FROM_NETWORK_FUNCTION,                                        CURLOPT_CONV_TO_NETWORK_FUNCTION, and                                        CURLOPT_CONV_FROM_UTF8_FUNCTION */    CURLE_SSL_CACERT_BADFILE, /* 77 - could not load CACERT file, missing                                        or wrong format */    CURLE_REMOTE_FILE_NOT_FOUND, /* 78 - remote file not found */    CURLE_SSH, /* 79 - error from the SSH layer, somewhat                                        generic so the error message will be of                                        interest when this has happened */        CURLE_SSL_SHUTDOWN_FAILED, /* 80 - Failed to shut down the SSL                                        connection */    CURLE_AGAIN, /* 81 - socket is not ready for send/recv,                                        wait till it‘s ready and try again (Added                                        in 7.18.2) */    CURLE_SSL_CRL_BADFILE, /* 82 - could not load CRL file, missing or                                        wrong format (Added in 7.19.0) */    CURLE_SSL_ISSUER_ERROR, /* 83 - Issuer check failed.  (Added in                                        7.19.0) */    CURL_LAST /* never use! */};