1libcurl-errors(3) libcurl errors libcurl-errors(3)
2
6 libcurl-errors - error codes in libcurl
7
9 This man page includes most, if not all, available error codes in
10 libcurl. Why they occur and possibly what you can do to fix the prob‐
11 lem are also included.
12
14 Almost all "easy" interface functions return a CURLcode error code. No
15 matter what, using the curl_easy_setopt(3) option CURLOPT_ERROR‐
16 BUFFER(3) is a good idea as it will give you a human readable error
17 string that may offer more details about the cause of the error than
18 just the error code. curl_easy_strerror(3) can be called to get an
19 error string from a given CURLcode number.
20 CURLcode is one of the following:
22 CURLE_OK (0)
24 All fine. Proceed as usual.
25 CURLE_UNSUPPORTED_PROTOCOL (1)
27 The URL you passed to libcurl used a protocol that this libcurl
28 does not support. The support might be a compile-time option
29 that you didn't use, it can be a misspelled protocol string or
30 just a protocol libcurl has no code for.
31 CURLE_FAILED_INIT (2)
33 Very early initialization code failed. This is likely to be an
34 internal error or problem, or a resource problem where something
35 fundamental couldn't get done at init time.
36 CURLE_URL_MALFORMAT (3)
38 The URL was not properly formatted.
39 CURLE_NOT_BUILT_IN (4)
41 A requested feature, protocol or option was not found built-in
42 in this libcurl due to a build-time decision. This means that a
43 feature or option was not enabled or explicitly disabled when
44 libcurl was built and in order to get it to function you have to
45 get a rebuilt libcurl.
46 CURLE_COULDNT_RESOLVE_PROXY (5)
48 Couldn't resolve proxy. The given proxy host could not be
49 resolved.
50 CURLE_COULDNT_RESOLVE_HOST (6)
52 Couldn't resolve host. The given remote host was not resolved.
53 CURLE_COULDNT_CONNECT (7)
55 Failed to connect() to host or proxy.
56 CURLE_FTP_WEIRD_SERVER_REPLY (8)
58 The server sent data libcurl couldn't parse. This error code is
59 used for more than just FTP and is aliased as
60 CURLE_WEIRD_SERVER_REPLY since 7.51.0.
61 CURLE_REMOTE_ACCESS_DENIED (9)
63 We were denied access to the resource given in the URL. For
64 FTP, this occurs while trying to change to the remote directory.
65 CURLE_FTP_ACCEPT_FAILED (10)
67 While waiting for the server to connect back when an active FTP
68 session is used, an error code was sent over the control connec‐
69 tion or similar.
70 CURLE_FTP_WEIRD_PASS_REPLY (11)
72 After having sent the FTP password to the server, libcurl
73 expects a proper reply. This error code indicates that an unex‐
74 pected code was returned.
75 CURLE_FTP_ACCEPT_TIMEOUT (12)
77 During an active FTP session while waiting for the server to
78 connect, the CURLOPT_ACCEPTTIMEOUT_MS(3) (or the internal
79 default) timeout expired.
80 CURLE_FTP_WEIRD_PASV_REPLY (13)
82 libcurl failed to get a sensible result back from the server as
83 a response to either a PASV or a EPSV command. The server is
84 flawed.
85 CURLE_FTP_WEIRD_227_FORMAT (14)
87 FTP servers return a 227-line as a response to a PASV command.
88 If libcurl fails to parse that line, this return code is passed
89 back.
90 CURLE_FTP_CANT_GET_HOST (15)
92 An internal failure to lookup the host used for the new connec‐
93 tion.
94 CURLE_HTTP2 (16)
96 A problem was detected in the HTTP2 framing layer. This is some‐
97 what generic and can be one out of several problems, see the
98 error buffer for details.
99 CURLE_FTP_COULDNT_SET_TYPE (17)
101 Received an error when trying to set the transfer mode to binary
102 or ASCII.
103 CURLE_PARTIAL_FILE (18)
105 A file transfer was shorter or larger than expected. This hap‐
106 pens when the server first reports an expected transfer size,
107 and then delivers data that doesn't match the previously given
108 size.
109 CURLE_FTP_COULDNT_RETR_FILE (19)
111 This was either a weird reply to a 'RETR' command or a zero byte
112 transfer complete.
113 CURLE_QUOTE_ERROR (21)
115 When sending custom "QUOTE" commands to the remote server, one
116 of the commands returned an error code that was 400 or higher
117 (for FTP) or otherwise indicated unsuccessful completion of the
118 command.
119 CURLE_HTTP_RETURNED_ERROR (22)
121 This is returned if CURLOPT_FAILONERROR(3) is set TRUE and the
122 HTTP server returns an error code that is >= 400.
123 CURLE_WRITE_ERROR (23)
125 An error occurred when writing received data to a local file, or
126 an error was returned to libcurl from a write callback.
127 CURLE_UPLOAD_FAILED (25)
129 Failed starting the upload. For FTP, the server typically denied
130 the STOR command. The error buffer usually contains the server's
131 explanation for this.
132 CURLE_READ_ERROR (26)
134 There was a problem reading a local file or an error returned by
135 the read callback.
136 CURLE_OUT_OF_MEMORY (27)
138 A memory allocation request failed. This is serious badness and
139 things are severely screwed up if this ever occurs.
140 CURLE_OPERATION_TIMEDOUT (28)
142 Operation timeout. The specified time-out period was reached
143 according to the conditions.
144 CURLE_FTP_PORT_FAILED (30)
146 The FTP PORT command returned error. This mostly happens when
147 you haven't specified a good enough address for libcurl to use.
148 See CURLOPT_FTPPORT(3).
149 CURLE_FTP_COULDNT_USE_REST (31)
151 The FTP REST command returned error. This should never happen if
152 the server is sane.
153 CURLE_RANGE_ERROR (33)
155 The server does not support or accept range requests.
156 CURLE_HTTP_POST_ERROR (34)
158 This is an odd error that mainly occurs due to internal confu‐
159 sion.
160 CURLE_SSL_CONNECT_ERROR (35)
162 A problem occurred somewhere in the SSL/TLS handshake. You
163 really want the error buffer and read the message there as it
164 pinpoints the problem slightly more. Could be certificates (file
165 formats, paths, permissions), passwords, and others.
166 CURLE_BAD_DOWNLOAD_RESUME (36)
168 The download could not be resumed because the specified offset
169 was out of the file boundary.
170 CURLE_FILE_COULDNT_READ_FILE (37)
172 A file given with FILE:// couldn't be opened. Most likely
173 because the file path doesn't identify an existing file. Did you
174 check file permissions?
175 CURLE_LDAP_CANNOT_BIND (38)
177 LDAP cannot bind. LDAP bind operation failed.
178 CURLE_LDAP_SEARCH_FAILED (39)
180 LDAP search failed.
181 CURLE_FUNCTION_NOT_FOUND (41)
183 Function not found. A required zlib function was not found.
184 CURLE_ABORTED_BY_CALLBACK (42)
186 Aborted by callback. A callback returned "abort" to libcurl.
187 CURLE_BAD_FUNCTION_ARGUMENT (43)
189 Internal error. A function was called with a bad parameter.
190 CURLE_INTERFACE_FAILED (45)
192 Interface error. A specified outgoing interface could not be
193 used. Set which interface to use for outgoing connections'
194 source IP address with CURLOPT_INTERFACE(3).
195 CURLE_TOO_MANY_REDIRECTS (47)
197 Too many redirects. When following redirects, libcurl hit the
198 maximum amount. Set your limit with CURLOPT_MAXREDIRS(3).
199 CURLE_UNKNOWN_OPTION (48)
201 An option passed to libcurl is not recognized/known. Refer to
202 the appropriate documentation. This is most likely a problem in
203 the program that uses libcurl. The error buffer might contain
204 more specific information about which exact option it concerns.
205 CURLE_TELNET_OPTION_SYNTAX (49)
207 A telnet option string was Illegally formatted.
208 CURLE_GOT_NOTHING (52)
210 Nothing was returned from the server, and under the circum‐
211 stances, getting nothing is considered an error.
212 CURLE_SSL_ENGINE_NOTFOUND (53)
214 The specified crypto engine wasn't found.
215 CURLE_SSL_ENGINE_SETFAILED (54)
217 Failed setting the selected SSL crypto engine as default!
218 CURLE_SEND_ERROR (55)
220 Failed sending network data.
221 CURLE_RECV_ERROR (56)
223 Failure with receiving network data.
224 CURLE_SSL_CERTPROBLEM (58)
226 problem with the local client certificate.
227 CURLE_SSL_CIPHER (59)
229 Couldn't use specified cipher.
230 CURLE_PEER_FAILED_VERIFICATION (60)
232 The remote server's SSL certificate or SSH md5 fingerprint was
233 deemed not OK. This error code has been unified with
234 CURLE_SSL_CACERT since 7.62.0. Its previous value was 51.
235 CURLE_BAD_CONTENT_ENCODING (61)
237 Unrecognized transfer encoding.
238 CURLE_LDAP_INVALID_URL (62)
240 Invalid LDAP URL.
241 CURLE_FILESIZE_EXCEEDED (63)
243 Maximum file size exceeded.
244 CURLE_USE_SSL_FAILED (64)
246 Requested FTP SSL level failed.
247 CURLE_SEND_FAIL_REWIND (65)
249 When doing a send operation curl had to rewind the data to
250 retransmit, but the rewinding operation failed.
251 CURLE_SSL_ENGINE_INITFAILED (66)
253 Initiating the SSL Engine failed.
254 CURLE_LOGIN_DENIED (67)
256 The remote server denied curl to login (Added in 7.13.1)
257 CURLE_TFTP_NOTFOUND (68)
259 File not found on TFTP server.
260 CURLE_TFTP_PERM (69)
262 Permission problem on TFTP server.
263 CURLE_REMOTE_DISK_FULL (70)
265 Out of disk space on the server.
266 CURLE_TFTP_ILLEGAL (71)
268 Illegal TFTP operation.
269 CURLE_TFTP_UNKNOWNID (72)
271 Unknown TFTP transfer ID.
272 CURLE_REMOTE_FILE_EXISTS (73)
274 File already exists and will not be overwritten.
275 CURLE_TFTP_NOSUCHUSER (74)
277 This error should never be returned by a properly functioning
278 TFTP server.
279 CURLE_CONV_FAILED (75)
281 Character conversion failed.
282 CURLE_CONV_REQD (76)
284 Caller must register conversion callbacks.
285 CURLE_SSL_CACERT_BADFILE (77)
287 Problem with reading the SSL CA cert (path? access rights?)
288 CURLE_REMOTE_FILE_NOT_FOUND (78)
290 The resource referenced in the URL does not exist.
291 CURLE_SSH (79)
293 An unspecified error occurred during the SSH session.
294 CURLE_SSL_SHUTDOWN_FAILED (80)
296 Failed to shut down the SSL connection.
297 CURLE_AGAIN (81)
299 Socket is not ready for send/recv wait till it's ready and try
300 again. This return code is only returned from curl_easy_recv(3)
301 and curl_easy_send(3) (Added in 7.18.2)
302 CURLE_SSL_CRL_BADFILE (82)
304 Failed to load CRL file (Added in 7.19.0)
305 CURLE_SSL_ISSUER_ERROR (83)
307 Issuer check failed (Added in 7.19.0)
308 CURLE_FTP_PRET_FAILED (84)
310 The FTP server does not understand the PRET command at all or
311 does not support the given argument. Be careful when using CUR‐
312 LOPT_CUSTOMREQUEST(3), a custom LIST command will be sent with
313 PRET CMD before PASV as well. (Added in 7.20.0)
314 CURLE_RTSP_CSEQ_ERROR (85)
316 Mismatch of RTSP CSeq numbers.
317 CURLE_RTSP_SESSION_ERROR (86)
319 Mismatch of RTSP Session Identifiers.
320 CURLE_FTP_BAD_FILE_LIST (87)
322 Unable to parse FTP file list (during FTP wildcard downloading).
323 CURLE_CHUNK_FAILED (88)
325 Chunk callback reported error.
326 CURLE_NO_CONNECTION_AVAILABLE (89)
328 (For internal use only, will never be returned by libcurl) No
329 connection available, the session will be queued. (added in
330 7.30.0)
331 CURLE_SSL_PINNEDPUBKEYNOTMATCH (90)
333 Failed to match the pinned key specified with CURLOPT_PINNEDPUB‐
334 LICKEY(3).
335 CURLE_SSL_INVALIDCERTSTATUS (91)
337 Status returned failure when asked with CURLOPT_SSL_VERIFYSTA‐
338 TUS(3).
339 CURLE_HTTP2_STREAM (92)
341 Stream error in the HTTP/2 framing layer.
342 CURLE_RECURSIVE_API_CALL (93)
344 An API function was called from inside a callback.
345 CURLE_AUTH_ERROR (94)
347 An authentication function returned an error.
348 CURLE_OBSOLETE*
350 These error codes will never be returned. They were used in an
351 old libcurl version and are currently unused.
352
354 This is the generic return code used by functions in the libcurl multi
355 interface. Also consider curl_multi_strerror(3).
356 CURLM_CALL_MULTI_PERFORM (-1)
358 This is not really an error. It means you should call
359 curl_multi_perform(3) again without doing select() or similar in
360 between. Before version 7.20.0 this could be returned by
361 curl_multi_perform(3), but in later versions this return code is
362 never used.
363 CURLM_OK (0)
365 Things are fine.
366 CURLM_BAD_HANDLE (1)
368 The passed-in handle is not a valid CURLM handle.
369 CURLM_BAD_EASY_HANDLE (2)
371 An easy handle was not good/valid. It could mean that it isn't
372 an easy handle at all, or possibly that the handle already is in
373 used by this or another multi handle.
374 CURLM_OUT_OF_MEMORY (3)
376 You are doomed.
377 CURLM_INTERNAL_ERROR (4)
379 This can only be returned if libcurl bugs. Please report it to
380 us!
381 CURLM_BAD_SOCKET (5)
383 The passed-in socket is not a valid one that libcurl already
384 knows about. (Added in 7.15.4)
385 CURLM_UNKNOWN_OPTION (6)
387 curl_multi_setopt() with unsupported option (Added in 7.15.4)
388 CURLM_ADDED_ALREADY (7)
390 An easy handle already added to a multi handle was attempted to
391 get added a second time. (Added in 7.32.1)
392 CURLM_RECURSIVE_API_CALL (8)
394 An API function was called from inside a callback.
395
397 The "share" interface will return a CURLSHcode to indicate when an
398 error has occurred. Also consider curl_share_strerror(3).
399 CURLSHE_OK (0)
401 All fine. Proceed as usual.
402 CURLSHE_BAD_OPTION (1)
404 An invalid option was passed to the function.
405 CURLSHE_IN_USE (2)
407 The share object is currently in use.
408 CURLSHE_INVALID (3)
410 An invalid share object was passed to the function.
411 CURLSHE_NOMEM (4)
413 Not enough memory was available. (Added in 7.12.0)
414 CURLSHE_NOT_BUILT_IN (5)
416 The requested sharing could not be done because the library you
417 use don't have that particular feature enabled. (Added in
418 7.23.0)
419
421 CURLUE_BAD_HANDLE (1)
422 An argument that should be a CURLU pointer was passed in as a
423 NULL.
424 CURLUE_BAD_PARTPOINTER (2)
426 A NULL pointer was passed to the 'part' argument of
427 curl_url_get(3).
428 CURLUE_MALFORMED_INPUT (3)
430 A malformed input was passed to a URL API function.
431 CURLUE_BAD_PORT_NUMBER (4)
433 The port number was not a decimal number between 0 and 65535.
434 CURLUE_UNSUPPORTED_SCHEME (5)
436 This libcurl build doesn't support the given URL scheme.
437 CURLUE_URLDECODE (6)
439 URL decode error, most likely because of rubbish in the input.
440 CURLUE_OUT_OF_MEMORY (7)
442 A memory function failed.
443 CURLUE_USER_NOT_ALLOWED (8)
445 Credentials was passed in the URL when prohibited.
446 CURLUE_UNKNOWN_PART (9)
448 An unknown part ID was passed to a URL API function.
449 CURLUE_NO_SCHEME (10)
451 There is no scheme part in the URL.
452 CURLUE_NO_USER (11)
454 There is no user part in the URL.
455 CURLUE_NO_PASSWORD (12)
457 There is no password part in the URL.
458 CURLUE_NO_OPTIONS (13)
460 There is no options part in the URL.
461 CURLUE_NO_HOST (14)
463 There is no host part in the URL.
464 CURLUE_NO_PORT (15)
466 There is no port part in the URL.
467 CURLUE_NO_QUERY (16)
469 There is no query part in the URL.
470 CURLUE_NO_FRAGMENT (17)
472 There is no fragment part in the URL.
473
475 curl_easy_strerror(3), curl_multi_strerror(3), curl_share_strerror(3),
476 CURLOPT_ERRORBUFFER(3), CURLOPT_VERBOSE(3), CURLOPT_DEBUGFUNCTION(3)
477libcurl 7.66.0 May 11, 2019 libcurl-errors(3)