1.SH FILES 2.I ~/.curlrc 3.RS 4Default config file, see --config for details. 5.SH ENVIRONMENT 6The environment variables can be specified in lower case or upper case. The 7lower case version has precedence. http_proxy is an exception as it is only 8available in lower case. 9 10Using an environment variable to set the proxy has the same effect as using 11the --proxy option. 12 13.IP "http_proxy [protocol://]<host>[:port]" 14Sets the proxy server to use for HTTP. 15.IP "HTTPS_PROXY [protocol://]<host>[:port]" 16Sets the proxy server to use for HTTPS. 17.IP "[url-protocol]_PROXY [protocol://]<host>[:port]" 18Sets the proxy server to use for [url-protocol], where the protocol is a 19protocol that curl supports and as specified in a URL. FTP, FTPS, POP3, IMAP, 20SMTP, LDAP etc. 21.IP "ALL_PROXY [protocol://]<host>[:port]" 22Sets the proxy server to use if no protocol-specific proxy is set. 23.IP "NO_PROXY <comma-separated list of hosts>" 24list of host names that shouldn't go through any proxy. If set to a asterisk 25\&'*' only, it matches all hosts. 26 27Since 7.53.0, this environment variable disable the proxy even if specify 28--proxy option. That is 29.B NO_PROXY=direct.example.com curl -x http://proxy.example.com 30.B http://direct.example.com 31accesses the target URL directly, and 32.B NO_PROXY=direct.example.com curl -x http://proxy.example.com 33.B http://somewhere.example.com 34accesses the target URL through proxy. 35 36.SH "PROXY PROTOCOL PREFIXES" 37Since curl version 7.21.7, the proxy string may be specified with a 38protocol:// prefix to specify alternative proxy protocols. 39 40If no protocol is specified in the proxy string or if the string doesn't match 41a supported one, the proxy will be treated as an HTTP proxy. 42 43The supported proxy protocol prefixes are as follows: 44.IP "http://" 45Makes it use it as a HTTP proxy. The default if no scheme prefix is used. 46.IP "https://" 47Makes it treated as a \fBHTTPS\fP proxy. 48.IP "socks4://" 49Makes it the equivalent of --socks4 50.IP "socks4a://" 51Makes it the equivalent of --socks4a 52.IP "socks5://" 53Makes it the equivalent of --socks5 54.IP "socks5h://" 55Makes it the equivalent of --socks5-hostname 56.SH EXIT CODES 57There are a bunch of different error codes and their corresponding error 58messages that may appear during bad conditions. At the time of this writing, 59the exit codes are: 60.IP 1 61Unsupported protocol. This build of curl has no support for this protocol. 62.IP 2 63Failed to initialize. 64.IP 3 65URL malformed. The syntax was not correct. 66.IP 4 67A feature or option that was needed to perform the desired request was not 68enabled or was explicitly disabled at build-time. To make curl able to do 69this, you probably need another build of libcurl! 70.IP 5 71Couldn't resolve proxy. The given proxy host could not be resolved. 72.IP 6 73Couldn't resolve host. The given remote host was not resolved. 74.IP 7 75Failed to connect to host. 76.IP 8 77Weird server reply. The server sent data curl couldn't parse. 78.IP 9 79FTP access denied. The server denied login or denied access to the particular 80resource or directory you wanted to reach. Most often you tried to change to a 81directory that doesn't exist on the server. 82.IP 10 83FTP accept failed. While waiting for the server to connect back when an active 84FTP session is used, an error code was sent over the control connection or 85similar. 86.IP 11 87FTP weird PASS reply. Curl couldn't parse the reply sent to the PASS request. 88.IP 12 89During an active FTP session while waiting for the server to connect back to 90curl, the timeout expired. 91.IP 13 92FTP weird PASV reply, Curl couldn't parse the reply sent to the PASV request. 93.IP 14 94FTP weird 227 format. Curl couldn't parse the 227-line the server sent. 95.IP 15 96FTP can't get host. Couldn't resolve the host IP we got in the 227-line. 97.IP 16 98HTTP/2 error. A problem was detected in the HTTP2 framing layer. This is 99somewhat generic and can be one out of several problems, see the error message 100for details. 101.IP 17 102FTP couldn't set binary. Couldn't change transfer method to binary. 103.IP 18 104Partial file. Only a part of the file was transferred. 105.IP 19 106FTP couldn't download/access the given file, the RETR (or similar) command 107failed. 108.IP 21 109FTP quote error. A quote command returned error from the server. 110.IP 22 111HTTP page not retrieved. The requested url was not found or returned another 112error with the HTTP error code being 400 or above. This return code only 113appears if --fail is used. 114.IP 23 115Write error. Curl couldn't write data to a local filesystem or similar. 116.IP 25 117FTP couldn't STOR file. The server denied the STOR operation, used for FTP 118uploading. 119.IP 26 120Read error. Various reading problems. 121.IP 27 122Out of memory. A memory allocation request failed. 123.IP 28 124Operation timeout. The specified time-out period was reached according to the 125conditions. 126.IP 30 127FTP PORT failed. The PORT command failed. Not all FTP servers support the PORT 128command, try doing a transfer using PASV instead! 129.IP 31 130FTP couldn't use REST. The REST command failed. This command is used for 131resumed FTP transfers. 132.IP 33 133HTTP range error. The range "command" didn't work. 134.IP 34 135HTTP post error. Internal post-request generation error. 136.IP 35 137SSL connect error. The SSL handshaking failed. 138.IP 36 139Bad download resume. Couldn't continue an earlier aborted download. 140.IP 37 141FILE couldn't read file. Failed to open the file. Permissions? 142.IP 38 143LDAP cannot bind. LDAP bind operation failed. 144.IP 39 145LDAP search failed. 146.IP 41 147Function not found. A required LDAP function was not found. 148.IP 42 149Aborted by callback. An application told curl to abort the operation. 150.IP 43 151Internal error. A function was called with a bad parameter. 152.IP 45 153Interface error. A specified outgoing interface could not be used. 154.IP 47 155Too many redirects. When following redirects, curl hit the maximum amount. 156.IP 48 157Unknown option specified to libcurl. This indicates that you passed a weird 158option to curl that was passed on to libcurl and rejected. Read up in the 159manual! 160.IP 49 161Malformed telnet option. 162.IP 51 163The peer's SSL certificate or SSH MD5 fingerprint was not OK. 164.IP 52 165The server didn't reply anything, which here is considered an error. 166.IP 53 167SSL crypto engine not found. 168.IP 54 169Cannot set SSL crypto engine as default. 170.IP 55 171Failed sending network data. 172.IP 56 173Failure in receiving network data. 174.IP 58 175Problem with the local certificate. 176.IP 59 177Couldn't use specified SSL cipher. 178.IP 60 179Peer certificate cannot be authenticated with known CA certificates. 180.IP 61 181Unrecognized transfer encoding. 182.IP 62 183Invalid LDAP URL. 184.IP 63 185Maximum file size exceeded. 186.IP 64 187Requested FTP SSL level failed. 188.IP 65 189Sending the data requires a rewind that failed. 190.IP 66 191Failed to initialise SSL Engine. 192.IP 67 193The user name, password, or similar was not accepted and curl failed to log in. 194.IP 68 195File not found on TFTP server. 196.IP 69 197Permission problem on TFTP server. 198.IP 70 199Out of disk space on TFTP server. 200.IP 71 201Illegal TFTP operation. 202.IP 72 203Unknown TFTP transfer ID. 204.IP 73 205File already exists (TFTP). 206.IP 74 207No such user (TFTP). 208.IP 75 209Character conversion failed. 210.IP 76 211Character conversion functions required. 212.IP 77 213Problem with reading the SSL CA cert (path? access rights?). 214.IP 78 215The resource referenced in the URL does not exist. 216.IP 79 217An unspecified error occurred during the SSH session. 218.IP 80 219Failed to shut down the SSL connection. 220.IP 82 221Could not load CRL file, missing or wrong format (added in 7.19.0). 222.IP 83 223Issuer check failed (added in 7.19.0). 224.IP 84 225The FTP PRET command failed 226.IP 85 227RTSP: mismatch of CSeq numbers 228.IP 86 229RTSP: mismatch of Session Identifiers 230.IP 87 231unable to parse FTP file list 232.IP 88 233FTP chunk callback reported error 234.IP 89 235No connection available, the session will be queued 236.IP 90 237SSL public key does not matched pinned public key 238.IP 91 239Invalid SSL certificate status. 240.IP 92 241Stream error in HTTP/2 framing layer. 242.IP XX 243More error codes will appear here in future releases. The existing ones 244are meant to never change. 245.SH AUTHORS / CONTRIBUTORS 246Daniel Stenberg is the main author, but the whole list of contributors is 247found in the separate THANKS file. 248.SH WWW 249https://curl.haxx.se 250.SH "SEE ALSO" 251.BR ftp (1), 252.BR wget (1) 253