PHP cURL Option Guide

cURL Options

PHP has a built-in implementation of cURL that is real nice. But it's format is completely difference than using cURL through the command line. This guide takes the options list from, and attempts to match each option up with it's command line counterpart, from cURL's man page. This will save you tons of time if you are converting scripts that use the command line cURL, to scripts that use PHP's native cURL.

For more info on using PHP's cURL implementation, check out

For the full, original list of PHP's cURL options, check out the curl_setopt( ) function

Boolean Options

CLI Flag curl_setopt( ) Description
-e/--referer "<url>;auto" CURLOPT_AUTOREFERER TRUE to automatically set the http referer header when following a redirect
-j/--junk-session-cookies CURLOPT_COOKIESESSION TRUE to discard all session cookies, to initiate a new session
--crlf CURLOPT_CRLF TRUE to convert Unix newlines to CRLF newlines on transfers
-f/--fail CURLOPT_FAILONERROR TRUE to fail silently on HTTP errors
-i/--include* CURLOPT_FILETIME TRUE to get modification date of file. *-i returns the full HTTP header, including the modification date.
-L/--location CURLOPT_FOLLOWLOCATION TRUE to follow any Location headers sent by server
--disable-eprt CURLOPT_FTP_USE_EPRT TRUE to use EPRT, FALSE to disable EPRT
--disable-epsv CURLOPT_FTP_USE_EPSV TRUE to use EPSV, FALSE to disable EPSV
-a/--append CURLOPT_FTPAPPEND TRUE to append to a file instead of overwriting it.
-l/--list-only CURLOPT_FTPLISTONLY TRUE to only list the names of an FTP directory
-i/--include CURLOPT_HEADER TRUE to include the header in the output
-G/--get CURLOPT_HTTPGET TRUE to reset the HTTP request method to GET
-p/--proxytunnel CURLOPT_HTTPPROXYTUNNEL TRUE to tunnel through a given HTTP proxy
-s/--silent CURLOPT_MUTE TRUE to be completely silent with regards to the cURL functions
-n/--netrc CURLOPT_NETRC TRUE to scan the ~/.netrc file to find a username and password for the remote site that a connection is being established with
-I/--head CURLOPT_NOBODY TRUE to exclude the body from the output. Request method is then set to HEAD.
-X/--request POST CURLOPT_POST TRUE to do a regular HTTP POST
-T/--upload-file <file> CURLOPT_PUT TRUE to HTTP PUT a file. The file to PUT must be set with CURLOPT_INFILE and CURLOPT_INFILESIZE
-k/--insecure CURLOPT_SSL_VERIFYPEER FALSE to stop cURL from verifying the peer's certificate
-B/--use-ascii CURLOPT_TRANSFERTEXT TRUE to use ASCII mode for FTP transfers
--location-trusted CURLOPT_UNRESTRICTED_AUTH TRUE to keep sending the username and password when following locations
-v/--verbose CURLOPT_VERBOSE TRUE to output verbose information

Integer Options

CLI Flag curl_setopt( ) Description
--connect-timeout <#> CURLOPT_CONNECTTIMEOUT The number of seconds to wait while trying to connect. Use 0 to wait indefinitely
--krb <level>
-Y/--speed-limit <speed> CURLOPT_LOW_SPEED_LIMIT The transfer speed, in bytes per second, that the transfer should be below during the count of CURLOPT_LOW_SPEED_TIME seconds before PHP considers the transfer too slow and aborts
-y/--speed-time <time> CURLOPT_LOW_SPEED_TIME The number of seconds the transfer speed should be below CURLOPT_LOW_SPEED_LIMIT before PHP considers the transfer too slow and aborts
--max-redirs <num> CURLOPT_MAXREDIRS The maximum amount of HTTP redirections to follow
CURLOPT_PROXYAUTH The HTTP authentication method(s) to use for the proxy connection
-x/--proxy <proxyhost[:port]> CURLOPT_PROXYPORT The port number of the proxy to connect to
-C/--continue-at <offset> CURLOPT_RESUME_FROM The offset, in bytes, to resume a transfer from
CURLOPT_SSLVERSION The SSL version (2 or 3) to use
-m/--max-time <seconds> CURLOPT_TIMEOUT The maximum number of seconds to allow cURL functions to execute
--limit-rate <speed> CURLOPT_MAX_RECV_SPEED_LARGE
If a transfer exceeds this speed (counted in bytes per second) on cumulative average during the transfer, the transfer will pause to keep the average rate less than or equal to the parameter value

String Options

CLI Flag curl_setopt( ) Description
--cacert <CA certificate> CURLOPT_CAINFO The name of a file holding one or more certificates to verify the peer with
--capath <CA certificate directory> CURLOPT_CAPATH A directory that holds multiple CA certificates
-b/--cookie <name=data> CURLOPT_COOKIE The contents of the "Cookie: " header to be used in the HTTP request
-b/--cookie <file> CURLOPT_COOKIEFILE The name of the file containing the cookie data
-c/--cookie-jar <file> CURLOPT_COOKIEJAR The name of a file to save all internal cookies to when the handle is closed
-X/--request <command> CURLOPT_CUSTOMREQUEST A custom request method to use instead of "GET" or "HEAD" when doing a HTTP request
--egd-file <file> CURLOPT_EGDSOCKET A filename to an Entropy Gathering Daemon socket
-H/--header "Accept-Encoding: gzip,deflate" CURLOPT_ENCODING The contents of the "Accept-Encoding: " header. This enables decoding of the response.
-P/--ftp-port <address> CURLOPT_FTPPORT The value which will be used to get the IP address to use for the FTP "POST" instruction. The "POST" instruction tells the remote server to connect to our specified IP address
--interface <name> CURLOPT_INTERFACE The name of the outgoing network interface to use. This can be an interface name, an IP address or a host name
--krb <level> CURLOPT_KRB4LEVEL The Kerberos 4 security level. Any of the following values (in order from least to most powerful) are valid: "clear", "safe", "confidential", "private"
-d/--data <data> CURLOPT_POSTFIELDS The full data to post in a HTTP "POST" operation. To post a file, prepend a filename with @ and use the full path. The filetype can be explicitly specified by following the filename with the type in the format ';type=mimetype'. This parameter can either be passed as a urlencoded string like 'para1=val1&para2=val2&...' or as an array with the field name as key and field data as value. If value is an array, the Content-Type header will be set to multipart/form-data. As of PHP 5.2.0, value must be an array if files are passed to this option with the @ prefix.
-x/--proxy <proxyhost[:port]> CURLOPT_PROXY The HTTP proxy to tunnel requests through
-U/--proxy-user <user:password> CURLOPT_PROXYUSERPWD A username and password formatted as "[username]:[password]" to use for the connection to the proxy
--random-file <file> CURLOPT_RANDOM_FILE A filename to be used to seed the random number generator for SSL
-r/--range <range> CURLOPT_RANGE Range(s) of data to retrieve in the format "X-Y" where X or Y are optional. HTTP transfers also support several intervals, separated with commas in the format "X-Y,N-M"
-e/--referer <URL> CURLOPT_REFERER The contents of the "Referer: " header to be used in a HTTP request
--ciphers <list of ciphers> CURLOPT_SSL_CIPHER_LIST A list of ciphers to use for SSL. For example, RC4-SHA and TLSv1 are valid cipher lists
-E/--cert <certificate[:password]> CURLOPT_SSLCERT The name of a file containing a PEM formatted certificate
-E/--cert <certificate[:password]> CURLOPT_SSLCERTPASSWD The password required to use the CURLOPT_SSLCERT certificate
--cert-type <type> CURLOPT_SSLCERTTYPE The format of the certificate. Supported formats are "PEM" (default), "DER", and "ENG"
--engine <name> CURLOPT_SSLENGINE The identifier for the crypto engine of the private SSL key specified in CURLOPT_SSLKEY
--key <key> CURLOPT_SSLKEY The name of a file containing a private SSL key
--pass <phrase> CURLOPT_SSLKEYPASSWD The secret password needed to use the private SSL key specified in CURLOPT_SSLKEY
--key-type <type> CURLOPT_SSLKEYTYPE The key type of the private SSL key specified in CURLOPT_SSLKEY. Supported key types are "PEM" (default), "DER", and "ENG"
-A/--user-agent <agent> CURLOPT_USERAGENT The contents of the "User-Agent: " header to be used in a HTTP request
-u/--user <user:password> CURLOPT_USERPWD A username and password formatted as "[username]:[password]" to use for the connection