Parameter sharing of the curl_setopt() function of the CURL method in PHP_PHP tutorial

PHP CURL curl_setopt 参数

bool curl_setopt (int ch, string option, mixed value)
curl_setopt()函数将为一个CURL会话设置选项。option参数是你想要的设置，value是这个选项给定的值。

下列选项的值将被作为长整形使用(在option参数中指定)：   
    CURLOPT_INFILESIZE : 当你上传一个文件到远程站点，这个选项告诉PHP你上传文件的大小。
    CURLOPT_VERBOSE : 如果你想CURL报告每一件意外的事情，设置这个选项为一个非零值。
    CURLOPT_HEADER : 如果你想把一个头包含在输出中，设置这个选项为一个非零值。
    CURLOPT_NOPROGRESS: 如果你不会PHP为CURL传输显示一个进程条，设置这个选项为一个非零值。注意：PHP自动设置这个选项为非零值，你应该仅仅为了调试的目的来改变这个选项。
    CURLOPT_NOBODY : 如果你不想在输出中包含body部分，设置这个选项为一个非零值。
    CURLOPT_FAILONERROR : 如果你想让PHP在发生错误(HTTP代码返回大于等于300)时，不显示，设置这个选项为一人非零值。默认行为是返回一个正常页，忽略代码。
    CURLOPT_UPLOAD: 如果你想让PHP为上传做准备，设置这个选项为一个非零值。
    CURLOPT_POST : 如果你想PHP去做一个正规的HTTP POST，设置这个选项为一个非零值。这个POST是普通的 application/x-www-from-urlencoded 类型，多数被HTML表单使用。
    CURLOPT_FTPLISTONLY : 设置这个选项为非零值，PHP将列出FTP的目录名列表。
    CURLOPT_FTPAPPEND : 设置这个选项为一个非零值，PHP将应用远程文件代替覆盖它。
    CURLOPT_NETRC : 设置这个选项为一个非零值，PHP将在你的 ~./netrc 文件中查找你要建立连接的远程站点的用户名及密码。
    CURLOPT_FOLLOWLOCATION : 设置这个选项为一个非零值(象 “Location: “)的头，服务器会把它当做HTTP头的一部分发送(注意这是递归的，PHP将发送形如 “Location: “的头)。
    CURLOPT_PUT : 设置这个选项为一个非零值去用HTTP上传一个文件。要上传这个文件必须设置CURLOPT_INFILE和CURLOPT_INFILESIZE选项.
    CURLOPT_MUTE : 设置这个选项为一个非零值，PHP对于CURL函数将完全沉默。
    CURLOPT_TIMEOUT : 设置一个长整形数，作为最大延续多少秒。
    CURLOPT_LOW_SPEED_LIMIT: 设置一个长整形数，控制传送多少字节。
    CURLOPT_LOW_SPEED_TIME : 设置一个长整形数，控制多少秒传送CURLOPT_LOW_SPEED_LIMIT规定的字节数。
    CURLOPT_RESUME_FROM : 传递一个包含字节偏移地址的长整形参数，(你想转移到的开始表单)。
    CURLOPT_SSLVERSION: 传递一个包含SSL版本的长参数。默认PHP将被它自己努力的确定，在更多的安全中你必须手工设置。
    CURLOPT_TIMECONDITION : 传递一个长参数，指定怎么处理CURLOPT_TIMEVALUE参数。你可以设置这个参数为TIMECOND_IFMODSINCE 或 TIMECOND_ISUNMODSINCE。这仅用于HTTP。
    CURLOPT_TIMEVALUE : 传递一个从1970-1-1开始到现在的秒数。这个时间将被CURLOPT_TIMEVALUE选项作为指定值使用，或被默认TIMECOND_IFMODSINCE使用。

The values ​​of the following options will be treated as strings:
CURLOPT_URL: This is the URL address you want to retrieve using PHP. You can also set this option during initialization with the curl_init() function.
CURLOPT_USERPWD: Pass a string in the form of [username]:[password] and use PHP to connect.
CURLOPT_PROXYUSERPWD: Pass a string in the format [username]:[password] to connect to the HTTP proxy.
CURLOPT_RANGE: Pass a range you want to specify. It should be in "X-Y" format, with X or Y being excluded. HTTP transfers also support several intervals, separated by commas (X-Y,N-M).
CURLOPT_POSTFIELDS: Pass a string containing all data as an HTTP "POST" operation.
CURLOPT_REFERER: A string containing a "referer" header in the HTTP request.
CURLOPT_USERAGENT: A string containing a "user-agent" header in the HTTP request.
CURLOPT_FTPPORT: Pass an IP address containing the IP address used by the ftp "POST" command. This POST command tells the remote server to connect to the IP address we specified. This string can be an IP address, a host name, a network interface name (under UNIX), or '-' (use the system default IP address).
CURLOPT_COOKIE: Pass a header connection containing an HTTP cookie.
CURLOPT_SSLCERT: Pass a string containing the certificate in PEM format.
CURLOPT_SSLCERTPASSWD: Pass a password containing the necessary password to use the CURLOPT_SSLCERT certificate.
CURLOPT_COOKIEFILE: Pass a string containing the name of the file containing cookie data. This cookie file can be in Netscape format, or it can be a stack of HTTP-style headers stored in the file.
CURLOPT_CUSTOMREQUEST: When making an HTTP request, pass a character to be used by GET or HEAD. Pass a string to be used instead of GET or HEAD when doing an HTTP request. This is useful for doing or another, more obscure, HTTP request. Note: Make sure your server supports Order not to do it yet. The following options require a file description (obtained by using the fopen() function):
CURLOPT_FILE: This file will be the output file you place the transfer, the default is STDOUT.
CURLOPT_INFILE: This file will be the input you transfer document.
CURLOPT_WRITEHEADER: This file contains the header part of your output.
CURLOPT_STDERR : This file has errors written instead of stderr. An example of obtaining a page that requires login. The current method is to log in once every time. People who need it will make improvements.

Example 1:

curl_close — 关闭一个curl会话
curl_copy_handle — 拷贝一个curl连接资源的所有内容和参数
curl_errno — 返回一个包含当前会话错误信息的数字编号
curl_error — 返回一个包含当前会话错误信息的字符串
curl_exec — 执行一个curl会话
curl_getinfo — 获取一个curl连接资源句柄的信息
curl_init — 初始化一个curl会话
curl_multi_add_handle — 向curl批处理会话中添加单独的curl句柄资源
curl_multi_close — 关闭一个批处理句柄资源
curl_multi_exec — 解析一个curl批处理句柄
curl_multi_getcontent — 返回获取的输出的文本流
curl_multi_info_read — 获取当前解析的curl的相关传输信息
curl_multi_init — 初始化一个curl批处理句柄资源
curl_multi_remove_handle — 移除curl批处理句柄资源中的某个句柄资源
curl_multi_select — Get all the sockets associated with the cURL extension, which can then be "selected"
curl_setopt_array — 以数组的形式为一个curl设置会话参数
curl_setopt — 为一个curl设置会话参数
curl_version — 获取curl相关的版本信息

curl_init()函数的作用初始化一个curl会话，curl_init()函数唯一的一个参数是可选的，表示一个url地址。
curl_exec()函数的作用是执行一个curl会话，唯一的参数是curl_init()函数返回的句柄。
curl_close()函数的作用是关闭一个curl会话，唯一的参数是curl_init()函数返回的句柄。

$ch = curl_init("http://www.baidu.com/");
curl_exec($ch);
curl_close($ch);
curl_version()函数的作用是获取curl相关的版本信息，curl_version()函数有一个参数，不清楚是做什么的

print_r(curl_version())
curl_getinfo()函数的作用是获取一个curl连接资源句柄的信息，curl_getinfo()函数有两个参数，第一个参数是curl的资源句柄，第二个参数是下面一些常量：

$ch = curl_init("http://www.baidu.com/");
print_r(curl_getinfo($ch));
可选的常量包括：
CURLINFO_EFFECTIVE_URL
最后一个有效的url地址
CURLINFO_HTTP_CODE
最后一个收到的HTTP代码
CURLINFO_FILETIME
远程获取文档的时间，如果无法获取，则返回值为“-1”
CURLINFO_TOTAL_TIME
最后一次传输所消耗的时间
CURLINFO_NAMELOOKUP_TIME
名称解析所消耗的时间
CURLINFO_CONNECT_TIME
建立连接所消耗的时间
CURLINFO_PRETRANSFER_TIME
从建立连接到准备传输所使用的时间
CURLINFO_STARTTRANSFER_TIME
从建立连接到传输开始所使用的时间
CURLINFO_REDIRECT_TIME
在事务传输开始前重定向所使用的时间
CURLINFO_SIZE_UPLOAD
上传数据量的总值
CURLINFO_SIZE_DOWNLOAD
下载数据量的总值
CURLINFO_SPEED_DOWNLOAD
平均下载速度
CURLINFO_SPEED_UPLOAD
平均上传速度
CURLINFO_HEADER_SIZE
header部分的大小
CURLINFO_HEADER_OUT
发送请求的字符串
CURLINFO_REQUEST_SIZE
在HTTP请求中有问题的请求的大小
CURLINFO_SSL_VERIFYRESULT
Result of SSL certification verification requested by setting CURLOPT_SSL_VERIFYPEER
CURLINFO_CONTENT_LENGTH_DOWNLOAD
从Content-Length: field中读取的下载内容长度
CURLINFO_CONTENT_LENGTH_UPLOAD
上传内容大小的说明
CURLINFO_CONTENT_TYPE
下载内容的“Content-type”值，NULL表示服务器没有发送有效的“Content-Type: header”
curl_setopt()函数的作用是为一个curl设置会话参数。curl_setopt_array()函数的作用是以数组的形式为一个curl设置会话参数。

$ch = curl_init();
$fp = fopen("example_homepage.txt", "w");
curl_setopt($ch, CURLOPT_FILE, $fp);
$options = array (
CURLOPT_URL => 'http://www.baidu.com/',
CURLOPT_HEADER => false
);
curl_setopt_array($ch, $options);
curl_exec ($ch);
curl_close($ch);
fclose($fp);
The parameters that can be set are:
CURLOPT_AUTOREFERER
Automatically set the referer information in the header
CURLOPT_BINARYTRANSFER
When CURLOPT_RETURNTRANSFER is enabled, the retrieved data will be returned
CURLOPT_COOKIESESSION
When enabled, curl will only pass one session cookie and ignore other cookies. By default, curl will return all cookies to the server. Session cookies refer to cookies that are used to determine whether the server-side session is valid.
CURLOPT_CRLF
When enabled, convert Unix line feed characters into carriage return and line feed characters.
CURLOPT_DNS_USE_GLOBAL_CACHE
When enabled, a global DNS cache is enabled. This item is thread-safe and defaults to true.
CURLOPT_FAILONERROR
Displays the HTTP status code. The default behavior is to ignore HTTP information with a number less than or equal to 400.
CURLOPT_FILETIME
When enabled, it will try to modify the information in the remote document. The result information will be returned through the CURLINFO_FILETIME option of the curl_getinfo() function.
CURLOPT_FOLLOWLOCATION
When enabled, the "Location:" returned by the server will be placed in the header and returned to the server recursively. Use CURLOPT_MAXREDIRS to limit the number of recursive returns.
CURLOPT_FORBID_REUSE
Forcibly disconnects after completing the interaction and cannot be reused.
CURLOPT_FRESH_CONNECT
Force a new connection to replace the one in the cache.
CURLOPT_FTP_USE_EPRT
TRUE to use EPRT (and LPRT) when doing active FTP downloads. Use FALSE to disable EPRT and LPRT and use PORT only.
Added in PHP 5.0.0.
CURLOPT_FTP_USE_EPSV
TRUE to first try an EPSV command for FTP transfers before reverting back to PASV. Set to FALSE to disable EPSV.
CURLOPT_FTPAPPEND
TRUE to append to the remote file instead of overwriting it.
CURLOPT_FTPASCII
An alias of CURLOPT_TRANSFERTEXT. Use that instead.
CURLOPT_FTPLISTONLY
TRUE to only list the names of an FTP directory.
CURLOPT_HEADER
When enabled, the header file information will be output as a data stream.
CURLOPT_HTTPGET
When enabled, the HTTP method will be set to GET. Because GET is the default, it is only used when it is modified.
CURLOPT_HTTPPROXYTUNNEL
When enabled, it will be transmitted through HTTP proxy.
CURLOPT_MUTE
Restore all modified parameters in the curl function to their default values.
CURLOPT_NETRC
After the connection is established, access the ~/.netrc file to obtain the username and password information to connect to the remote site.
CURLOPT_NOBODY
When enabled, the body part in HTML will not be output.
CURLOPT_NOPROGRESS
When enabled, turn off the progress bar of curl transmission. The default setting of this item is true
CURLOPT_NOSIGNAL
When enabled, ignore all signals passed by curl to PHP. This item is turned on by default during SAPI multi-thread transmission.
CURLOPT_POST
When enabled, a regular POST request will be sent of type: application/x-www-form-urlencoded, just like a form submission.
CURLOPT_PUT
When enabled, HTTP is allowed to send files. CURLOPT_INFILE and CURLOPT_INFILESIZE must be set at the same time.
CURLOPT_RETURNTRANSFER
The information obtained by curl_exec() is returned in the form of a file stream instead of being output directly.
CURLOPT_SSL_VERIFYPEER
FALSE to stop cURL from verifying the peer's certificate. Alternate certificates to verify against can be specified with the CURLOPT_CAINFO option or a certificate directory can be specified with the CURLOPT_CAPATH option. CURLOPT_SSL_VERIFYHOST may also need to be TRUE or FALSE if CURLOPT_SSL_VERIFYPEER is disabled (it defaults to 2). TRUE by default as of cURL 7.10. Default bundle installed as of cURL 7.10.
CURLOPT_TRANSFERTEXT
TRUE to use ASCII mode for FTP transfers. For LDAP, it retrieves data in plain text instead of HTML. On Windows systems, it will not set STDOUT to binary mode.
CURLOPT_UNRESTRICTED_AUTH
Continuously append username and password information to multiple locations in the header generated using CURLOPT_FOLLOWLOCATION, even if the domain name has changed .
CURLOPT_UPLOAD
Allow file transfer when enabled
CURLOPT_VERBOSE
When enabled, all information will be reported and stored in STDERR or the specified CURLOPT_STDERR
CURLOPT_BUFFERSIZE
Read in the data obtained each time The size of the cache, this value will be filled every time.
CURLOPT_CLOSEPOLICY
It is either CURLCLOSEPOLICY_LEAST_RECENTLY_USED or CURLCLOSEPOLICY_OLDEST. There are three others, but curl does not support them yet. .
CURLOPT_CONNECTTIMEOUT
The time to wait before initiating a connection. If set to 0, there will be no waiting.
CURLOPT_DNS_CACHE_TIMEOUT
Set the time to save DNS information in memory, the default is 120 seconds.
CURLOPT_FTPSSLAUTH
The FTP authentication method (when is activated): CURLFTPAUTH_SSL (try SSL first), CURLFTPAUTH_TLS (try TLS first), or CURLFTPAUTH_DEFAULT (let cURL decide).
CURLOPT_HTTP_VERSION
Set curl to use HTTP protocol, CURL_HTTP_VERSION_NONE (let curl decide for itself), CURL_HTTP_VERSION_1_0 (HTTP/1.0), CURL_HTTP_VERSION_1_1 (HTTP/1.1)
CURLOPT_HTTPAUTH
HTTP verification method used, optional values ​​are: CURLAUTH_BASIC, CURLAUTH_DIGEST, CURLAUTH_GSSNEGO TIATE,CURLAUTH_NTLM , CURLAUTH_ANY, CURLAUTH_ANYSAFE, you can use the "|" operator to separate multiple values, curl allows the server to choose the best supported value, CURLAUTH_ANY is equivalent to CURLAUTH_BASIC | CURLAUTH_DIGEST | CURLAUTH_GSSNEGOTIATE | CURLAUTH_NTLM, CURLAUTH_ANYSAFE is equivalent to CURLAUTH_DIGEST | CURLAUTH_GSSNE GOTIATE | CURLAUTH_NTLM
CURLOPT_INFILESIZE
Set the size of the uploaded file
CURLOPT_LOW_SPEED_LIMIT
When the transfer speed is less than CURLOPT_LOW_SPEED_LIMIT, PHP will use CURLOPT_LOW_SPEED_TIME to determine whether to cancel the transfer because it is too slow.
CURLOPT_LOW_SPEED_TIME
The number of seconds the transfer should be below CURLOPT_LOW_SPEED_LIMIT for PHP to consider the transfer too slow and abort. transmission.
CURLOPT_MAXCONNECTS
The maximum number of connections allowed. If exceeded, CURLOPT_CLOSEPOLICY will be used to determine which connections should be stopped.
CURLOPT_MAXREDIRS
Specify the maximum number of HTTP redirects. This option is used together with CURLOPT_FOLLOWLOCATION. For proxy authentication, only CURLAUTH_BASIC and CURLAUTH_NTLM are currently supported.
CURLOPT_PROXYPORT
The port number of the proxy to connect to. This port number can also be set in CURLOPT_PROXY. CURLPROXY_SOCKS5.
CURLOPT_RESUME_FROM
Pass a byte offset when resuming the transfer (used to resume the transfer)
CURLOPT_SSL_VERIFYHOST
1 to check the existence of a common name in the SSL peer certificate.
2 to check the existence of a common name and also verify that it matches the hostname provided.
CURLOPT_SSLVERSION
The SSL version (2 or 3) to use. By default PHP will try to determine this itself, although in some cases this must be set manually.
CURLOPT_TIMECONDITION
If it has been edited after a certain time specified by CURLOPT_TIMEVALUE, use CURL_TIMECOND_IFMODSINCE to return the page, if it has not been modified and CURLOPT_HEADER is true, return a "304 Not Modified" header, if CURLOPT_HEADER is false, use CURL_TIMECOND_ISUNMODSINCE, the default value is CURL_TIMECOND_IFMODSINCE
CURLOPT_TIMEOUT
Set the maximum number of seconds that curl is allowed to execute
CURLOPT_TIMEVALUE
Set the time used by CURLOPT_TIMECONDITION poke , used by default is CURL_TIMECOND_IFMODSINCE
CURLOPT_CAINFO
The name of a file holding one or more certificates to verify the peer with. This only makes sense when used in combination with CURLOPT_SSL_VERIFYPEER.
CURLOPT_CAPATH
A directory that holds multiple CA certificates. Use this option alongside CURLOPT_SSL_VERIFYPEER.
CURLOPT_COOKIE
Set the content of the "Set-Cookie:" part of the HTTP request.
CURLOPT_COOKIEFILE
The name of the file containing cookie information. This cookie file can be Netscape format or HTTP style header information.
CURLOPT_COOKIEJAR
After the connection is closed, the name of the file to store cookie information
CURLOPT_CUSTOMREQUEST
A custom request method to use instead of "GET" or "HEAD" when doing a HTTP request. This is useful for doing "DELETE" or other, more obscure HTTP requests. Valid values ​​are things like "GET", "POST", "CONNECT" and so on; i.e. Do not enter a whole HTTP request line here. For instance, entering "GET /index .html HTTP/1.0rnrn" would be incorrect.
Note: Don't do this without making sure the server supports the custom request method first.
CURLOPT_EGBSOCKET
Like CURLOPT_RANDOM_FILE, except a filename to an Entropy Gathering Daemon socket.
CURLOPT_ENCODING
The contents of the "Accept-Encoding:" part of the header. The supported encoding formats are: "identity", "deflate", "gzip". If set to an empty string, it means that all encoding formats are supported
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. The string may be a plain IP address, a hostname, a network interface name (under Unix), or just a plain '-' to use the systems default IP address.
CURLOPT_INTERFACE
The name used in the external network interface, which can be an interface name, IP or host name.
CURLOPT_KRB4LEVEL
KRB4(Kerberos 4)安全级别的设置，可以是一下几个值之一："clear"，"safe"，"confidential"，"private"。默认的值 为"private"，设置为null的时候表示禁用KRB4，现在KRB4安全仅能在FTP传输中使用。
CURLOPT_POSTFIELDS
在HTTP中的“POST”操作。如果要传送一个文件，需要一个@开头的文件名
CURLOPT_PROXY
设置通过的HTTP代理服务器
CURLOPT_PROXYUSERPWD
连接到代理服务器的，格式为“[username]:[password]”的用户名和密码。
CURLOPT_RANDOM_FILE
设定存放SSL用到的随机数种子的文件名称
CURLOPT_RANGE
设置HTTP传输范围，可以用“X-Y”的形式设置一个传输区间，如果有多个HTTP传输，则使用逗号分隔多个值，形如："X-Y,N-M"。
CURLOPT_REFERER
设置header中"Referer: " 部分的值。
CURLOPT_SSL_CIPHER_LIST
A list of ciphers to use for SSL. For example, RC4-SHA and TLSv1 are valid cipher lists.
CURLOPT_SSLCERT
传递一个包含PEM格式证书的字符串。
CURLOPT_SSLCERTPASSWD
传递一个包含使用CURLOPT_SSLCERT证书必需的密码。
CURLOPT_SSLCERTTYPE
The format of the certificate. Supported formats are "PEM" (default), "DER", and "ENG".
CURLOPT_SSLENGINE
The identifier for the crypto engine of the private SSL key specified in CURLOPT_SSLKEY.
CURLOPT_SSLENGINE_DEFAULT
The identifier for the crypto engine used for asymmetric crypto operations.
CURLOPT_SSLKEY
The name of a file containing a private SSL key.
CURLOPT_SSLKEYPASSWD
The secret password needed to use the private SSL key specified in CURLOPT_SSLKEY.
Note: Since this option contains a sensitive password, remember to keep the PHP script it is contained within safe.
CURLOPT_SSLKEYTYPE
The key type of the private SSL key specified in CURLOPT_SSLKEY. Supported key types are "PEM" (default), "DER", and "ENG".
CURLOPT_URL
需要获取的URL地址，也可以在PHP的curl_init()函数中设置。
CURLOPT_USERAGENT
在HTTP请求中包含一个”user-agent”头的字符串。
CURLOPT_USERPWD
传递一个连接中需要的用户名和密码，格式为：“[username]:[password]”。
CURLOPT_HTTP200ALIASES
设置不再以error的形式来处理HTTP 200的响应，格式为一个数组。
CURLOPT_HTTPHEADER
设置一个header中传输内容的数组。
CURLOPT_POSTQUOTE
An array of FTP commands to execute on the server after the FTP request has been performed.
CURLOPT_QUOTE
An array of FTP commands to execute on the server prior to the FTP request.
CURLOPT_FILE
设置输出文件的位置，值是一个资源类型，默认为STDOUT (浏览器)。
CURLOPT_INFILE
在上传文件的时候需要读取的文件地址，值是一个资源类型。
CURLOPT_STDERR
设置一个错误输出地址，值是一个资源类型，取代默认的STDERR。
CURLOPT_WRITEHEADER
设置header部分内容的写入的文件地址，值是一个资源类型。
CURLOPT_HEADERFUNCTION
设置一个回调函数，这个函数有两个参数，第一个是curl的资源句柄，第二个是输出的header数据。header数据的输出必须依赖这个函数，返回已写入的数据大小。
CURLOPT_PASSWDFUNCTION
设置一个回调函数，有三个参数，第一个是curl的资源句柄，第二个是一个密码提示符，第三个参数是密码长度允许的最大值。返回密码的值。
CURLOPT_READFUNCTION
设置一个回调函数，有两个参数，第一个是curl的资源句柄，第二个是读取到的数据。数据读取必须依赖这个函数。返回读取数据的大小，比如0或者EOF。
CURLOPT_WRITEFUNCTION
设置一个回调函数，有两个参数，第一个是curl的资源句柄，第二个是写入的数据。数据写入必须依赖这个函数。返回精确的已写入数据的大小
curl_copy_handle()函数的作用是拷贝一个curl连接资源的所有内容和参数

$ch = curl_init("http://www.baidu.com/");
$another = curl_copy_handle($ch);
curl_exec($another);
curl_close($another );
The function of curl_error() function is to return a string containing error information of the current session.
The function of curl_errno() is to return a numeric number containing error information of the current session.
The curl_multi_init() function is used to initialize a curl batch handle resource.
The curl_multi_add_handle() function is used to add individual curl handle resources to the curl batch session. The curl_multi_add_handle() function has two parameters. The first parameter represents a curl batch handle resource, and the second parameter represents a separate curl handle resource.
The function of the curl_multi_exec() function is to parse a curl batch handle. The curl_multi_exec() function has two parameters. The first parameter represents a batch handle resource, and the second parameter is a reference value parameter, indicating the remaining The number of individual curl handle resources that need to be processed.
The curl_multi_remove_handle() function represents the removal of a handle resource in the curl batch handle resource. The curl_multi_remove_handle() function has two parameters. The first parameter represents a curl batch handle resource, and the second parameter represents a separate The curl handle resource.
The curl_multi_close() function is used to close a batch handle resource.

$ch1 = curl_init();
$ch2 = curl_init();
curl_setopt($ch1, CURLOPT_URL, "http://www.baidu.com/");
curl_setopt($ ch1, CURLOPT_HEADER, 0);
curl_setopt($ch2, CURLOPT_URL, "http://www.google.com/");
curl_setopt($ch2, CURLOPT_HEADER, 0);
$mh = curl_multi_init();
curl_multi_add_handle($mh,$ch1);
curl_multi_add_handle($mh,$ch2);
do {
curl_multi_exec($mh,$flag);
} while ($flag > 0);
curl_multi_remove_handle($mh,$ch1);
curl_multi_remove_handle($mh,$ch2);
curl_multi_close($mh);
The role of curl_multi_getcontent() function Returns the text stream of the obtained output when CURLOPT_RETURNTRANSFER is set.
The curl_multi_info_read() function is used to obtain the relevant transmission information of the currently parsed curl.
curl_multi_select()
Get all the sockets associated with the cURL extension, which can then be "selected"