Provided by: libcurl4-doc_7.58.0-2ubuntu3.24_all bug

NAME

       libcurl-errors - error codes in libcurl

DESCRIPTION

       This man page includes most, if not all, available error codes in libcurl.  Why they occur
       and possibly what you can do to fix the problem are also included.

CURLcode

       Almost all "easy" interface functions return a CURLcode error code. No matter what,  using
       the curl_easy_setopt(3) option CURLOPT_ERRORBUFFER(3) is a good idea as it will give you a
       human readable error string that may offer more details about the cause of the error  than
       just  the  error  code.  curl_easy_strerror(3) can be called to get an error string from a
       given CURLcode number.

       CURLcode is one of the following:

       CURLE_OK (0)
              All fine. Proceed as usual.

       CURLE_UNSUPPORTED_PROTOCOL (1)
              The URL you passed to libcurl used a protocol that this libcurl does  not  support.
              The  support  might  be  a  compile-time  option  that  you didn't use, it can be a
              misspelled protocol string or just a protocol libcurl has no code for.

       CURLE_FAILED_INIT (2)
              Very early initialization code failed. This is likely to be an  internal  error  or
              problem,  or  a  resource  problem where something fundamental couldn't get done at
              init time.

       CURLE_URL_MALFORMAT (3)
              The URL was not properly formatted.

       CURLE_NOT_BUILT_IN (4)
              A requested feature, protocol or option was not found built-in in this libcurl  due
              to  a  build-time  decision. This means that a feature or option was not enabled or
              explicitly disabled when libcurl was built and in order to get it to  function  you
              have to get a rebuilt libcurl.

       CURLE_COULDNT_RESOLVE_PROXY (5)
              Couldn't resolve proxy. The given proxy host could not be resolved.

       CURLE_COULDNT_RESOLVE_HOST (6)
              Couldn't resolve host. The given remote host was not resolved.

       CURLE_COULDNT_CONNECT (7)
              Failed to connect() to host or proxy.

       CURLE_FTP_WEIRD_SERVER_REPLY (8)
              The  server sent data libcurl couldn't parse. This error code is used for more than
              just FTP and is aliased as CURLE_WEIRD_SERVER_REPLY since 7.51.0.

       CURLE_REMOTE_ACCESS_DENIED (9)
              We were denied access to the resource given in the URL.  For FTP, this occurs while
              trying to change to the remote directory.

       CURLE_FTP_ACCEPT_FAILED (10)
              While waiting for the server to connect back when an active FTP session is used, an
              error code was sent over the control connection or similar.

       CURLE_FTP_WEIRD_PASS_REPLY (11)
              After having sent the FTP password to the server, libcurl expects a  proper  reply.
              This error code indicates that an unexpected code was returned.

       CURLE_FTP_ACCEPT_TIMEOUT (12)
              During  an  active  FTP  session  while  waiting  for  the  server  to connect, the
              CURLOPT_ACCEPTTIMEOUT_MS(3) (or the internal default) timeout expired.

       CURLE_FTP_WEIRD_PASV_REPLY (13)
              libcurl failed to get a sensible result back from  the  server  as  a  response  to
              either a PASV or a EPSV command. The server is flawed.

       CURLE_FTP_WEIRD_227_FORMAT (14)
              FTP  servers return a 227-line as a response to a PASV command. If libcurl fails to
              parse that line, this return code is passed back.

       CURLE_FTP_CANT_GET_HOST (15)
              An internal failure to lookup the host used for the new connection.

       CURLE_HTTP2 (16)
              A problem was detected in the HTTP2 framing layer. This is somewhat generic and can
              be one out of several problems, see the error buffer for details.

       CURLE_FTP_COULDNT_SET_TYPE (17)
              Received an error when trying to set the transfer mode to binary or ASCII.

       CURLE_PARTIAL_FILE (18)
              A  file  transfer was shorter or larger than expected. This happens when the server
              first reports an expected transfer size, and then delivers data that doesn't  match
              the previously given size.

       CURLE_FTP_COULDNT_RETR_FILE (19)
              This was either a weird reply to a 'RETR' command or a zero byte transfer complete.

       CURLE_QUOTE_ERROR (21)
              When  sending  custom  "QUOTE"  commands  to the remote server, one of the commands
              returned an error code that was 400 or higher  (for  FTP)  or  otherwise  indicated
              unsuccessful completion of the command.

       CURLE_HTTP_RETURNED_ERROR (22)
              This  is returned if CURLOPT_FAILONERROR(3) is set TRUE and the HTTP server returns
              an error code that is >= 400.

       CURLE_WRITE_ERROR (23)
              An error occurred when writing received data to a  local  file,  or  an  error  was
              returned to libcurl from a write callback.

       CURLE_UPLOAD_FAILED (25)
              Failed  starting the upload. For FTP, the server typically denied the STOR command.
              The error buffer usually contains the server's explanation for this.

       CURLE_READ_ERROR (26)
              There was a problem reading a local file or an error returned by the read callback.

       CURLE_OUT_OF_MEMORY (27)
              A memory allocation request failed. This is serious badness and things are severely
              screwed up if this ever occurs.

       CURLE_OPERATION_TIMEDOUT (28)
              Operation  timeout.  The  specified  time-out  period  was reached according to the
              conditions.

       CURLE_FTP_PORT_FAILED (30)
              The FTP PORT command returned error. This mostly happens when you haven't specified
              a good enough address for libcurl to use. See CURLOPT_FTPPORT(3).

       CURLE_FTP_COULDNT_USE_REST (31)
              The  FTP  REST  command  returned  error. This should never happen if the server is
              sane.

       CURLE_RANGE_ERROR (33)
              The server does not support or accept range requests.

       CURLE_HTTP_POST_ERROR (34)
              This is an odd error that mainly occurs due to internal confusion.

       CURLE_SSL_CONNECT_ERROR (35)
              A problem occurred somewhere in the SSL/TLS handshake. You really  want  the  error
              buffer  and read the message there as it pinpoints the problem slightly more. Could
              be certificates (file formats, paths, permissions), passwords, and others.

       CURLE_BAD_DOWNLOAD_RESUME (36)
              The download could not be resumed because the specified offset was out of the  file
              boundary.

       CURLE_FILE_COULDNT_READ_FILE (37)
              A  file  given  with  FILE:// couldn't be opened. Most likely because the file path
              doesn't identify an existing file. Did you check file permissions?

       CURLE_LDAP_CANNOT_BIND (38)
              LDAP cannot bind. LDAP bind operation failed.

       CURLE_LDAP_SEARCH_FAILED (39)
              LDAP search failed.

       CURLE_FUNCTION_NOT_FOUND (41)
              Function not found. A required zlib function was not found.

       CURLE_ABORTED_BY_CALLBACK (42)
              Aborted by callback. A callback returned "abort" to libcurl.

       CURLE_BAD_FUNCTION_ARGUMENT (43)
              Internal error. A function was called with a bad parameter.

       CURLE_INTERFACE_FAILED (45)
              Interface error. A specified outgoing  interface  could  not  be  used.  Set  which
              interface   to   use   for   outgoing   connections'   source   IP   address   with
              CURLOPT_INTERFACE(3).

       CURLE_TOO_MANY_REDIRECTS (47)
              Too many redirects. When following redirects, libcurl hit the maximum amount.   Set
              your limit with CURLOPT_MAXREDIRS(3).

       CURLE_UNKNOWN_OPTION (48)
              An  option  passed  to  libcurl  is  not recognized/known. Refer to the appropriate
              documentation. This is most likely a problem in the program that uses libcurl.  The
              error  buffer  might  contain more specific information about which exact option it
              concerns.

       CURLE_TELNET_OPTION_SYNTAX (49)
              A telnet option string was Illegally formatted.

       CURLE_PEER_FAILED_VERIFICATION (51)
              The remote server's SSL certificate or SSH md5 fingerprint was deemed not OK.

       CURLE_GOT_NOTHING (52)
              Nothing was returned from the server, and under the circumstances, getting  nothing
              is considered an error.

       CURLE_SSL_ENGINE_NOTFOUND (53)
              The specified crypto engine wasn't found.

       CURLE_SSL_ENGINE_SETFAILED (54)
              Failed setting the selected SSL crypto engine as default!

       CURLE_SEND_ERROR (55)
              Failed sending network data.

       CURLE_RECV_ERROR (56)
              Failure with receiving network data.

       CURLE_SSL_CERTPROBLEM (58)
              problem with the local client certificate.

       CURLE_SSL_CIPHER (59)
              Couldn't use specified cipher.

       CURLE_SSL_CACERT (60)
              Peer certificate cannot be authenticated with known CA certificates.

       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)
              When  doing  a  send  operation  curl had to rewind the data to retransmit, but the
              rewinding operation failed.

       CURLE_SSL_ENGINE_INITFAILED (66)
              Initiating the SSL Engine failed.

       CURLE_LOGIN_DENIED (67)
              The remote server denied curl to login (Added in 7.13.1)

       CURLE_TFTP_NOTFOUND (68)
              File not found on TFTP server.

       CURLE_TFTP_PERM (69)
              Permission problem on TFTP server.

       CURLE_REMOTE_DISK_FULL (70)
              Out of disk space on the server.

       CURLE_TFTP_ILLEGAL (71)
              Illegal TFTP operation.

       CURLE_TFTP_UNKNOWNID (72)
              Unknown TFTP transfer ID.

       CURLE_REMOTE_FILE_EXISTS (73)
              File already exists and will not be overwritten.

       CURLE_TFTP_NOSUCHUSER (74)
              This error should never be returned by a properly functioning TFTP server.

       CURLE_CONV_FAILED (75)
              Character conversion failed.

       CURLE_CONV_REQD (76)
              Caller must register conversion callbacks.

       CURLE_SSL_CACERT_BADFILE (77)
              Problem with reading the SSL CA cert (path? access rights?)

       CURLE_REMOTE_FILE_NOT_FOUND (78)
              The resource referenced in the URL does not exist.

       CURLE_SSH (79)
              An unspecified error occurred during the SSH session.

       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.  This  return
              code  is  only  returned  from  curl_easy_recv(3)  and  curl_easy_send(3) (Added in
              7.18.2)

       CURLE_SSL_CRL_BADFILE (82)
              Failed to load CRL file (Added in 7.19.0)

       CURLE_SSL_ISSUER_ERROR (83)
              Issuer check failed (Added in 7.19.0)

       CURLE_FTP_PRET_FAILED (84)
              The FTP server does not understand the PRET command at all or does not support  the
              given  argument.  Be  careful  when  using  CURLOPT_CUSTOMREQUEST(3), a custom LIST
              command will be sent with PRET CMD before PASV as well. (Added in 7.20.0)

       CURLE_RTSP_CSEQ_ERROR (85)
              Mismatch of RTSP CSeq numbers.

       CURLE_RTSP_SESSION_ERROR (86)
              Mismatch of RTSP Session Identifiers.

       CURLE_FTP_BAD_FILE_LIST (87)
              Unable to parse FTP file list (during FTP wildcard downloading).

       CURLE_CHUNK_FAILED (88)
              Chunk callback reported error.

       CURLE_NO_CONNECTION_AVAILABLE (89)
              (For internal use only, will never be returned by libcurl) No connection available,
              the session will be queued. (added in 7.30.0)

       CURLE_SSL_PINNEDPUBKEYNOTMATCH (90)
              Failed to match the pinned key specified with CURLOPT_PINNEDPUBLICKEY(3).

       CURLE_SSL_INVALIDCERTSTATUS (91)
              Status returned failure when asked with CURLOPT_SSL_VERIFYSTATUS(3).

       CURLE_HTTP2_STREAM (92)
              Stream error in the HTTP/2 framing layer.

       CURLE_OBSOLETE*
              These  error codes will never be returned. They were used in an old libcurl version
              and are currently unused.

CURLMcode

       This is the generic return code used by functions in the  libcurl  multi  interface.  Also
       consider curl_multi_strerror(3).

       CURLM_CALL_MULTI_PERFORM (-1)
              This  is  not really an error. It means you should call curl_multi_perform(3) again
              without doing select() or similar in between. Before version 7.20.0 this  could  be
              returned  by curl_multi_perform(3), but in later versions this return code is never
              used.

       CURLM_OK (0)
              Things are fine.

       CURLM_BAD_HANDLE (1)
              The passed-in handle is not a valid CURLM handle.

       CURLM_BAD_EASY_HANDLE (2)
              An easy handle was not good/valid. It could mean that it isn't an  easy  handle  at
              all,  or  possibly  that  the  handle  already  is in used by this or another multi
              handle.

       CURLM_OUT_OF_MEMORY (3)
              You are doomed.

       CURLM_INTERNAL_ERROR (4)
              This can only be returned if libcurl bugs. Please report it to us!

       CURLM_BAD_SOCKET (5)
              The passed-in socket is not a valid one that libcurl already knows  about.   (Added
              in 7.15.4)

       CURLM_UNKNOWN_OPTION (6)
              curl_multi_setopt() with unsupported option (Added in 7.15.4)

       CURLM_ADDED_ALREADY (7)
              An  easy handle already added to a multi handle was attempted to get added a second
              time. (Added in 7.32.1)

CURLSHcode

       The "share" interface will return a CURLSHcode to indicate when  an  error  has  occurred.
       Also consider curl_share_strerror(3).

       CURLSHE_OK (0)
              All fine. Proceed as usual.

       CURLSHE_BAD_OPTION (1)
              An invalid option was passed to the function.

       CURLSHE_IN_USE (2)
              The share object is currently in use.

       CURLSHE_INVALID (3)
              An invalid share object was passed to the function.

       CURLSHE_NOMEM (4)
              Not enough memory was available.  (Added in 7.12.0)

       CURLSHE_NOT_BUILT_IN (5)
              The requested sharing could not be done because the library you use don't have that
              particular feature enabled. (Added in 7.23.0)

SEE ALSO

       curl_easy_strerror(3),           curl_multi_strerror(3),           curl_share_strerror(3),
       CURLOPT_ERRORBUFFER(3), CURLOPT_VERBOSE(3), CURLOPT_DEBUGFUNCTION(3)