libcurl-errors.3 18 KB

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  8. .\" * Copyright (C) 1998 - 2022, Daniel Stenberg, <daniel@haxx.se>, et al.
  9. .\" *
  10. .\" * This software is licensed as described in the file COPYING, which
  11. .\" * you should have received as part of this distribution. The terms
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  13. .\" *
  14. .\" * You may opt to use, copy, modify, merge, publish, distribute and/or sell
  15. .\" * copies of the Software, and permit persons to whom the Software is
  16. .\" * furnished to do so, under the terms of the COPYING file.
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  21. .\" * SPDX-License-Identifier: curl
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  24. .\"
  25. .TH libcurl-errors 3 "23 Nov 2021" "libcurl 7.81.0" "libcurl errors"
  26. .SH NAME
  27. libcurl-errors \- error codes in libcurl
  28. .SH DESCRIPTION
  29. This man page includes most, if not all, available error codes in libcurl.
  30. Why they occur and possibly what you can do to fix the problem are also included.
  31. .SH "CURLcode"
  32. Almost all "easy" interface functions return a CURLcode error code. No matter
  33. what, using the \fIcurl_easy_setopt(3)\fP option \fICURLOPT_ERRORBUFFER(3)\fP
  34. is a good idea as it will give you a human readable error string that may
  35. offer more details about the cause of the error than just the error code.
  36. \fIcurl_easy_strerror(3)\fP can be called to get an error string from a given
  37. CURLcode number.
  38. CURLcode is one of the following:
  39. .IP "CURLE_OK (0)"
  40. All fine. Proceed as usual.
  41. .IP "CURLE_UNSUPPORTED_PROTOCOL (1)"
  42. The URL you passed to libcurl used a protocol that this libcurl does not
  43. support. The support might be a compile-time option that you did not use, it
  44. can be a misspelled protocol string or just a protocol libcurl has no code
  45. for.
  46. .IP "CURLE_FAILED_INIT (2)"
  47. Early initialization code failed. This is likely to be an internal error or
  48. problem, or a resource problem where something fundamental could not get done
  49. at init time.
  50. .IP "CURLE_URL_MALFORMAT (3)"
  51. The URL was not properly formatted.
  52. .IP "CURLE_NOT_BUILT_IN (4)"
  53. A requested feature, protocol or option was not found built-in in this libcurl
  54. due to a build-time decision. This means that a feature or option was not
  55. enabled or explicitly disabled when libcurl was built and in order to get it
  56. to function you have to get a rebuilt libcurl.
  57. .IP "CURLE_COULDNT_RESOLVE_PROXY (5)"
  58. Could not resolve proxy. The given proxy host could not be resolved.
  59. .IP "CURLE_COULDNT_RESOLVE_HOST (6)"
  60. Could not resolve host. The given remote host was not resolved.
  61. .IP "CURLE_COULDNT_CONNECT (7)"
  62. Failed to connect() to host or proxy.
  63. .IP "CURLE_WEIRD_SERVER_REPLY (8)"
  64. The server sent data libcurl could not parse. This error code was known as as
  65. \fICURLE_FTP_WEIRD_SERVER_REPLY\fP before 7.51.0.
  66. .IP "CURLE_REMOTE_ACCESS_DENIED (9)"
  67. We were denied access to the resource given in the URL. For FTP, this occurs
  68. while trying to change to the remote directory.
  69. .IP "CURLE_FTP_ACCEPT_FAILED (10)"
  70. While waiting for the server to connect back when an active FTP session is
  71. used, an error code was sent over the control connection or similar.
  72. .IP "CURLE_FTP_WEIRD_PASS_REPLY (11)"
  73. After having sent the FTP password to the server, libcurl expects a proper
  74. reply. This error code indicates that an unexpected code was returned.
  75. .IP "CURLE_FTP_ACCEPT_TIMEOUT (12)"
  76. During an active FTP session while waiting for the server to connect, the
  77. \fICURLOPT_ACCEPTTIMEOUT_MS(3)\fP (or the internal default) timeout expired.
  78. .IP "CURLE_FTP_WEIRD_PASV_REPLY (13)"
  79. libcurl failed to get a sensible result back from the server as a response to
  80. either a PASV or a EPSV command. The server is flawed.
  81. .IP "CURLE_FTP_WEIRD_227_FORMAT (14)"
  82. FTP servers return a 227-line as a response to a PASV command. If libcurl
  83. fails to parse that line, this return code is passed back.
  84. .IP "CURLE_FTP_CANT_GET_HOST (15)"
  85. An internal failure to lookup the host used for the new connection.
  86. .IP "CURLE_HTTP2 (16)"
  87. A problem was detected in the HTTP2 framing layer. This is somewhat generic
  88. and can be one out of several problems, see the error buffer for details.
  89. .IP "CURLE_FTP_COULDNT_SET_TYPE (17)"
  90. Received an error when trying to set the transfer mode to binary or ASCII.
  91. .IP "CURLE_PARTIAL_FILE (18)"
  92. A file transfer was shorter or larger than expected. This happens when the
  93. server first reports an expected transfer size, and then delivers data that
  94. does not match the previously given size.
  95. .IP "CURLE_FTP_COULDNT_RETR_FILE (19)"
  96. This was either a weird reply to a 'RETR' command or a zero byte transfer
  97. complete.
  98. .IP "Obsolete error (20)"
  99. Not used in modern versions.
  100. .IP "CURLE_QUOTE_ERROR (21)"
  101. When sending custom "QUOTE" commands to the remote server, one of the commands
  102. returned an error code that was 400 or higher (for FTP) or otherwise
  103. indicated unsuccessful completion of the command.
  104. .IP "CURLE_HTTP_RETURNED_ERROR (22)"
  105. This is returned if \fICURLOPT_FAILONERROR(3)\fP is set TRUE and the HTTP
  106. server returns an error code that is >= 400.
  107. .IP "CURLE_WRITE_ERROR (23)"
  108. An error occurred when writing received data to a local file, or an error was
  109. returned to libcurl from a write callback.
  110. .IP "Obsolete error (24)"
  111. Not used in modern versions.
  112. .IP "CURLE_UPLOAD_FAILED (25)"
  113. Failed starting the upload. For FTP, the server typically denied the STOR
  114. command. The error buffer usually contains the server's explanation for this.
  115. .IP "CURLE_READ_ERROR (26)"
  116. There was a problem reading a local file or an error returned by the read
  117. callback.
  118. .IP "CURLE_OUT_OF_MEMORY (27)"
  119. A memory allocation request failed. This is serious badness and
  120. things are severely screwed up if this ever occurs.
  121. .IP "CURLE_OPERATION_TIMEDOUT (28)"
  122. Operation timeout. The specified time-out period was reached according to the
  123. conditions.
  124. .IP "Obsolete error (29)"
  125. Not used in modern versions.
  126. .IP "CURLE_FTP_PORT_FAILED (30)"
  127. The FTP PORT command returned error. This mostly happens when you have not
  128. specified a good enough address for libcurl to use. See
  129. \fICURLOPT_FTPPORT(3)\fP.
  130. .IP "CURLE_FTP_COULDNT_USE_REST (31)"
  131. The FTP REST command returned error. This should never happen if the server is
  132. sane.
  133. .IP "Obsolete error (32)"
  134. Not used in modern versions.
  135. .IP "CURLE_RANGE_ERROR (33)"
  136. The server does not support or accept range requests.
  137. .IP "CURLE_HTTP_POST_ERROR (34)"
  138. This is an odd error that mainly occurs due to internal confusion.
  139. .IP "CURLE_SSL_CONNECT_ERROR (35)"
  140. A problem occurred somewhere in the SSL/TLS handshake. You really want the
  141. error buffer and read the message there as it pinpoints the problem slightly
  142. more. Could be certificates (file formats, paths, permissions), passwords, and
  143. others.
  144. .IP "CURLE_BAD_DOWNLOAD_RESUME (36)"
  145. The download could not be resumed because the specified offset was out of the
  146. file boundary.
  147. .IP "CURLE_FILE_COULDNT_READ_FILE (37)"
  148. A file given with FILE:// could not be opened. Most likely because the file
  149. path does not identify an existing file. Did you check file permissions?
  150. .IP "CURLE_LDAP_CANNOT_BIND (38)"
  151. LDAP cannot bind. LDAP bind operation failed.
  152. .IP "CURLE_LDAP_SEARCH_FAILED (39)"
  153. LDAP search failed.
  154. .IP "Obsolete error (40)"
  155. Not used in modern versions.
  156. .IP "CURLE_FUNCTION_NOT_FOUND (41)"
  157. Function not found. A required zlib function was not found.
  158. .IP "CURLE_ABORTED_BY_CALLBACK (42)"
  159. Aborted by callback. A callback returned "abort" to libcurl.
  160. .IP "CURLE_BAD_FUNCTION_ARGUMENT (43)"
  161. A function was called with a bad parameter.
  162. .IP "Obsolete error (44)"
  163. Not used in modern versions.
  164. .IP "CURLE_INTERFACE_FAILED (45)"
  165. Interface error. A specified outgoing interface could not be used. Set which
  166. interface to use for outgoing connections' source IP address with
  167. \fICURLOPT_INTERFACE(3)\fP.
  168. .IP "Obsolete error (46)"
  169. Not used in modern versions.
  170. .IP "CURLE_TOO_MANY_REDIRECTS (47)"
  171. Too many redirects. When following redirects, libcurl hit the maximum amount.
  172. Set your limit with \fICURLOPT_MAXREDIRS(3)\fP.
  173. .IP "CURLE_UNKNOWN_OPTION (48)"
  174. An option passed to libcurl is not recognized/known. Refer to the appropriate
  175. documentation. This is most likely a problem in the program that uses
  176. libcurl. The error buffer might contain more specific information about which
  177. exact option it concerns.
  178. .IP "CURLE_SETOPT_OPTION_SYNTAX (49)"
  179. An option passed in to a setopt was wrongly formatted. See error message for
  180. details about what option.
  181. .IP "Obsolete errors (50-51)"
  182. Not used in modern versions.
  183. .IP "CURLE_GOT_NOTHING (52)"
  184. Nothing was returned from the server, and under the circumstances, getting
  185. nothing is considered an error.
  186. .IP "CURLE_SSL_ENGINE_NOTFOUND (53)"
  187. The specified crypto engine was not found.
  188. .IP "CURLE_SSL_ENGINE_SETFAILED (54)"
  189. Failed setting the selected SSL crypto engine as default.
  190. .IP "CURLE_SEND_ERROR (55)"
  191. Failed sending network data.
  192. .IP "CURLE_RECV_ERROR (56)"
  193. Failure with receiving network data.
  194. .IP "Obsolete error (57)"
  195. Not used in modern versions.
  196. .IP "CURLE_SSL_CERTPROBLEM (58)"
  197. problem with the local client certificate.
  198. .IP "CURLE_SSL_CIPHER (59)"
  199. Could not use specified cipher.
  200. .IP "CURLE_PEER_FAILED_VERIFICATION (60)"
  201. The remote server's SSL certificate or SSH fingerprint was deemed not OK.
  202. This error code has been unified with CURLE_SSL_CACERT since 7.62.0. Its
  203. previous value was 51.
  204. .IP "CURLE_BAD_CONTENT_ENCODING (61)"
  205. Unrecognized transfer encoding.
  206. .IP "Obsolete error (62)"
  207. Not used in modern versions.
  208. .IP "CURLE_FILESIZE_EXCEEDED (63)"
  209. Maximum file size exceeded.
  210. .IP "CURLE_USE_SSL_FAILED (64)"
  211. Requested FTP SSL level failed.
  212. .IP "CURLE_SEND_FAIL_REWIND (65)"
  213. When doing a send operation curl had to rewind the data to retransmit, but the
  214. rewinding operation failed.
  215. .IP "CURLE_SSL_ENGINE_INITFAILED (66)"
  216. Initiating the SSL Engine failed.
  217. .IP "CURLE_LOGIN_DENIED (67)"
  218. The remote server denied curl to login (Added in 7.13.1)
  219. .IP "CURLE_TFTP_NOTFOUND (68)"
  220. File not found on TFTP server.
  221. .IP "CURLE_TFTP_PERM (69)"
  222. Permission problem on TFTP server.
  223. .IP "CURLE_REMOTE_DISK_FULL (70)"
  224. Out of disk space on the server.
  225. .IP "CURLE_TFTP_ILLEGAL (71)"
  226. Illegal TFTP operation.
  227. .IP "CURLE_TFTP_UNKNOWNID (72)"
  228. Unknown TFTP transfer ID.
  229. .IP "CURLE_REMOTE_FILE_EXISTS (73)"
  230. File already exists and will not be overwritten.
  231. .IP "CURLE_TFTP_NOSUCHUSER (74)"
  232. This error should never be returned by a properly functioning TFTP server.
  233. .IP "Obsolete error (75-76)"
  234. Not used in modern versions.
  235. .IP "CURLE_SSL_CACERT_BADFILE (77)"
  236. Problem with reading the SSL CA cert (path? access rights?)
  237. .IP "CURLE_REMOTE_FILE_NOT_FOUND (78)"
  238. The resource referenced in the URL does not exist.
  239. .IP "CURLE_SSH (79)"
  240. An unspecified error occurred during the SSH session.
  241. .IP "CURLE_SSL_SHUTDOWN_FAILED (80)"
  242. Failed to shut down the SSL connection.
  243. .IP "CURLE_AGAIN (81)"
  244. Socket is not ready for send/recv wait till it's ready and try again. This
  245. return code is only returned from \fIcurl_easy_recv(3)\fP and
  246. \fIcurl_easy_send(3)\fP (Added in 7.18.2)
  247. .IP "CURLE_SSL_CRL_BADFILE (82)"
  248. Failed to load CRL file (Added in 7.19.0)
  249. .IP "CURLE_SSL_ISSUER_ERROR (83)"
  250. Issuer check failed (Added in 7.19.0)
  251. .IP "CURLE_FTP_PRET_FAILED (84)"
  252. The FTP server does not understand the PRET command at all or does not support
  253. the given argument. Be careful when using \fICURLOPT_CUSTOMREQUEST(3)\fP, a
  254. custom LIST command will be sent with the PRET command before PASV as
  255. well. (Added in 7.20.0)
  256. .IP "CURLE_RTSP_CSEQ_ERROR (85)"
  257. Mismatch of RTSP CSeq numbers.
  258. .IP "CURLE_RTSP_SESSION_ERROR (86)"
  259. Mismatch of RTSP Session Identifiers.
  260. .IP "CURLE_FTP_BAD_FILE_LIST (87)"
  261. Unable to parse FTP file list (during FTP wildcard downloading).
  262. .IP "CURLE_CHUNK_FAILED (88)"
  263. Chunk callback reported error.
  264. .IP "CURLE_NO_CONNECTION_AVAILABLE (89)"
  265. (For internal use only, will never be returned by libcurl) No connection
  266. available, the session will be queued. (added in 7.30.0)
  267. .IP "CURLE_SSL_PINNEDPUBKEYNOTMATCH (90)"
  268. Failed to match the pinned key specified with \fICURLOPT_PINNEDPUBLICKEY(3)\fP.
  269. .IP "CURLE_SSL_INVALIDCERTSTATUS (91)"
  270. Status returned failure when asked with \fICURLOPT_SSL_VERIFYSTATUS(3)\fP.
  271. .IP "CURLE_HTTP2_STREAM (92)"
  272. Stream error in the HTTP/2 framing layer.
  273. .IP "CURLE_RECURSIVE_API_CALL (93)"
  274. An API function was called from inside a callback.
  275. .IP "CURLE_AUTH_ERROR (94)"
  276. An authentication function returned an error.
  277. .IP "CURLE_HTTP3 (95)"
  278. A problem was detected in the HTTP/3 layer. This is somewhat generic and can
  279. be one out of several problems, see the error buffer for details.
  280. .IP "CURLE_QUIC_CONNECT_ERROR (96)"
  281. QUIC connection error. This error may be caused by an SSL library error. QUIC
  282. is the protocol used for HTTP/3 transfers.
  283. .IP "CURLE_PROXY (97)"
  284. Proxy handshake error. \fICURLINFO_PROXY_ERROR(3)\fP provides extra details on
  285. the specific problem.
  286. .IP "CURLE_SSL_CLIENTCERT (98)"
  287. SSL Client Certificate required.
  288. .IP "CURLE_UNRECOVERABLE_POLL (99)"
  289. An internal call to poll() or select() returned error that is not recoverable.
  290. .IP "CURLE_OBSOLETE*"
  291. These error codes will never be returned. They were used in an old libcurl
  292. version and are currently unused.
  293. .SH "CURLMcode"
  294. This is the generic return code used by functions in the libcurl multi
  295. interface. Also consider \fIcurl_multi_strerror(3)\fP.
  296. .IP "CURLM_CALL_MULTI_PERFORM (-1)"
  297. This is not really an error. It means you should call
  298. \fIcurl_multi_perform(3)\fP again without doing select() or similar in
  299. between. Before version 7.20.0 (released on February 9 2010) this could be returned by
  300. \fIcurl_multi_perform(3)\fP, but in later versions this return code is never
  301. used.
  302. .IP "CURLM_CALL_MULTI_SOCKET (-1)"
  303. An alias for \fICURLM_CALL_MULTI_PERFORM\fP. Never returned by modern libcurl
  304. versions.
  305. .IP "CURLM_OK (0)"
  306. Things are fine.
  307. .IP "CURLM_BAD_HANDLE (1)"
  308. The passed-in handle is not a valid \fICURLM\fP handle.
  309. .IP "CURLM_BAD_EASY_HANDLE (2)"
  310. An easy handle was not good/valid. It could mean that it is not an easy handle
  311. at all, or possibly that the handle already is in use by this or another multi
  312. handle.
  313. .IP "CURLM_OUT_OF_MEMORY (3)"
  314. You are doomed.
  315. .IP "CURLM_INTERNAL_ERROR (4)"
  316. This can only be returned if libcurl bugs. Please report it to us!
  317. .IP "CURLM_BAD_SOCKET (5)"
  318. The passed-in socket is not a valid one that libcurl already knows about.
  319. (Added in 7.15.4)
  320. .IP "CURLM_UNKNOWN_OPTION (6)"
  321. curl_multi_setopt() with unsupported option
  322. (Added in 7.15.4)
  323. .IP "CURLM_ADDED_ALREADY (7)"
  324. An easy handle already added to a multi handle was attempted to get added a
  325. second time. (Added in 7.32.1)
  326. .IP "CURLM_RECURSIVE_API_CALL (8)"
  327. An API function was called from inside a callback.
  328. .IP "CURLM_WAKEUP_FAILURE (9)"
  329. Wake up is unavailable or failed.
  330. .IP "CURLM_BAD_FUNCTION_ARGUMENT (10)"
  331. A function was called with a bad parameter.
  332. .IP "CURLM_ABORTED_BY_CALLBACK (11)"
  333. A multi handle callback returned error.
  334. .IP "CURLM_UNRECOVERABLE_POLL (12)"
  335. An internal call to poll() or select() returned error that is not recoverable.
  336. .SH "CURLSHcode"
  337. The "share" interface will return a \fBCURLSHcode\fP to indicate when an error
  338. has occurred. Also consider \fIcurl_share_strerror(3)\fP.
  339. .IP "CURLSHE_OK (0)"
  340. All fine. Proceed as usual.
  341. .IP "CURLSHE_BAD_OPTION (1)"
  342. An invalid option was passed to the function.
  343. .IP "CURLSHE_IN_USE (2)"
  344. The share object is currently in use.
  345. .IP "CURLSHE_INVALID (3)"
  346. An invalid share object was passed to the function.
  347. .IP "CURLSHE_NOMEM (4)"
  348. Not enough memory was available.
  349. (Added in 7.12.0)
  350. .IP "CURLSHE_NOT_BUILT_IN (5)"
  351. The requested sharing could not be done because the library you use do not have
  352. that particular feature enabled. (Added in 7.23.0)
  353. .SH "CURLUcode"
  354. The URL interface will return a \fICURLUcode\fP to indicate when an error has
  355. occurred. Also consider \fIcurl_url_strerror(3)\fP.
  356. .IP "CURLUE_BAD_HANDLE (1)"
  357. An invalid URL handle was passed as argument.
  358. .IP "CURLUE_BAD_PARTPOINTER (2)"
  359. An invalid 'part' argument was passed as argument.
  360. .IP "CURLUE_MALFORMED_INPUT (3)"
  361. A malformed input was passed to a URL API function.
  362. .IP "CURLUE_BAD_PORT_NUMBER (4)"
  363. The port number was not a decimal number between 0 and 65535.
  364. .IP "CURLUE_UNSUPPORTED_SCHEME (5)"
  365. This libcurl build does not support the given URL scheme.
  366. .IP "CURLUE_URLDECODE (6)"
  367. URL decode error, most likely because of rubbish in the input.
  368. .IP "CURLUE_OUT_OF_MEMORY (7)"
  369. A memory function failed.
  370. .IP "CURLUE_USER_NOT_ALLOWED (8)"
  371. Credentials was passed in the URL when prohibited.
  372. .IP "CURLUE_UNKNOWN_PART (9)"
  373. An unknown part ID was passed to a URL API function.
  374. .IP "CURLUE_NO_SCHEME (10)"
  375. There is no scheme part in the URL.
  376. .IP "CURLUE_NO_USER (11)"
  377. There is no user part in the URL.
  378. .IP "CURLUE_NO_PASSWORD (12)"
  379. There is no password part in the URL.
  380. .IP "CURLUE_NO_OPTIONS (13)"
  381. There is no options part in the URL.
  382. .IP "CURLUE_NO_HOST (14)"
  383. There is no host part in the URL.
  384. .IP "CURLUE_NO_PORT (15)"
  385. There is no port part in the URL.
  386. .IP "CURLUE_NO_QUERY (16)"
  387. There is no query part in the URL.
  388. .IP "CURLUE_NO_FRAGMENT (17)"
  389. There is no fragment part in the URL.
  390. .IP "CURLUE_NO_ZONEID (18)"
  391. There is no zone id set in the URL.
  392. .IP "CURLUE_BAD_FILE_URL (19)"
  393. The file:// URL is invalid.
  394. .IP "CURLUE_BAD_FRAGMENT (20)"
  395. The fragment part of the URL contained bad or invalid characters.
  396. .IP "CURLUE_BAD_HOSTNAME (21)"
  397. The hostname contained bad or invalid characters.
  398. .IP "CURLUE_BAD_IPV6 (22)"
  399. The IPv6 address hostname contained bad or invalid characters.
  400. .IP "CURLUE_BAD_LOGIN (23)"
  401. The login part of the URL contained bad or invalid characters.
  402. .IP "CURLUE_BAD_PASSWORD (24)"
  403. The password part of the URL contained bad or invalid characters.
  404. .IP "CURLUE_BAD_PATH (25)"
  405. The path part of the URL contained bad or invalid characters.
  406. .IP "CURLUE_BAD_QUERY (26)"
  407. The query part of the URL contained bad or invalid characters.
  408. .IP "CURLUE_BAD_SCHEME (27)"
  409. The scheme part of the URL contained bad or invalid characters.
  410. .IP "CURLUE_BAD_SLASHES (28)"
  411. The URL contained an invalid number of slashes.
  412. .IP "CURLUE_BAD_USER (29)"
  413. The user part of the URL contained bad or invalid characters.
  414. .SH "SEE ALSO"
  415. .BR curl_easy_strerror "(3), " curl_multi_strerror "(3), "
  416. .BR curl_share_strerror "(3), " curl_url_strerror "(3), "
  417. .BR CURLOPT_ERRORBUFFER "(3), " CURLOPT_VERBOSE "(3), "
  418. .BR CURLOPT_DEBUGFUNCTION "(3)"