1.编译zlib

wget http://zlib.net/zlib-1.2.11.tar.gz
tar -xzf zlib-1.2.11.tar.gz
cd zlib-1.2.11/
./configure --prefix=/home/const
make && make install

2.编译c-ares

wget https://c-ares.haxx.se/download/c-ares-1.15.0.tar.gz
tar xvf c-ares-1.15.0.tar.gz
cd c-ares-1.15.0
../configure --prefix=/home/const
make && make install

3.编译OpenSSL

wget https://www.openssl.org/source/openssl-1.1.1k.tar.gz
tar xvf openssl-1.1.1k.tar.gz
./Configure --prefix=/home/const no-asm -shared linux-x86_64
make && make install

4.编译cURL

wget https://curl.se/download/curl-7.76.1.tar.xz 
tar xvf curl-7.76.1.tar.xz 
cd curl-7.76.1
./configure --prefix=/home/const CPPFLAGS="-I/home/const/include" LDFLAGS="-L/home/const/lib" LIBS=" -lssl -lcrypto -lz -ldl -lpthread"  --disable-werror --enable-curldebug --with-ssl=/home/const --enable-zlib --enable-ares

1. Go run shell script or Go run shell string

curl := "curl -v https://const.net.cn"
cmd := exec.Command("bash", "-c", curl)
stdout, err := cmd.CombinedOutput()
if err != nil {
    fmt.Println("curl " + err.Error())
    return
}
fmt.Println(string(stdout)) 

2.输出结果

• Uses proxy env variable https_proxy == 'socks5://127.0.0.1:1080'
• Trying 127.0.0.1:1080...

• TCP_NODELAY set % Total % Received % Xferd Average Speed Time Time Time Current

                               Dload  Upload   Total   Spent    Left  Speed   0     0    0     0    0     0      0      0 --:--:-- --:--:--

  --:--:-- 0

• SOCKS5 communication to const.net.cn:443
• SOCKS5 connect to IPv4 43.129.233.128:443 (locally resolved)
• SOCKS5 request granted.
• Connected to 127.0.0.1 (127.0.0.1) port 1080 (#0)
• ALPN, offering h2
• ALPN, offering http/1.1
• successfully set certificate verify locations:
• CAfile: /etc/ssl/certs/ca-certificates.crt CApath: /etc/ssl/certs } [5 bytes data]
• TLSv1.3 (OUT), TLS handshake, Client hello (1): } [512 bytes data]
• TLSv1.3 (IN), TLS handshake, Server hello (2): { [122 bytes data]
• TLSv1.3 (IN), TLS handshake, Encrypted Extensions (8): { [25 bytes data]
• TLSv1.3 (IN), TLS handshake, Certificate (11): { [2780 bytes data]
• TLSv1.3 (IN), TLS handshake, CERT verify (15): { [264 bytes data]
• TLSv1.3 (IN), TLS handshake, Finished (20): { [52 bytes data]
• TLSv1.3 (OUT), TLS change cipher, Change cipher spec (1): } [1 bytes data]
• TLSv1.3 (OUT), TLS handshake, Finished (20): } [52 bytes data]
• SSL connection using TLSv1.3 / TLS_AES_256_GCM_SHA384
• ALPN, server accepted to use http/1.1
• Server certificate:
• subject: CN=const.net.cn
• start date: May 19 00:00:00 2021 GMT
• expire date: May 18 23:59:59 2022 GMT
• subjectAltName: host "const.net.cn" matched cert's "const.net.cn"
• issuer: C=CN; O=TrustAsia Technologies, Inc.; OU=Domain Validated SSL; CN=TrustAsia TLS RSA CA
• SSL certificate verify ok. } [5 bytes data]

GET / HTTP/1.1
Host: const.net.cn
User-Agent: curl/7.68.0
Accept: /

......

0、curl 显示连接的常用方法

curl -d "hello=world" https://const.net.cn/test/ --verbose

输出结果：
...

• Server certificate:
• subject: CN=const.net.cn
• start date: May 19 00:00:00 2021 GMT
• expire date: May 18 23:59:59 2022 GMT
• subjectAltName: host "const.net.cn" matched cert's "const.net.cn"
• issuer: C=CN; O=TrustAsia Technologies, Inc.; OU=Domain Validated SSL; CN=TrustAsia TLS RSA CA
• SSL certificate verify ok.

POST /test/ HTTP/1.1
Host: const.net.cn
User-Agent: curl/7.68.0
Accept: /
Content-Length: 11
Content-Type: application/x-www-form-urlencoded

• upload completely sent off: 11 out of 11 bytes
  ...

1、curl 显示 form 数据

curl -d "hello=world" https://const.net.cn/test/ --trace-ascii /dev/stdout

输出结果：
0000: POST /test/ HTTP/1.1
0016: Host: const.net.cn
002a: User-Agent: curl/7.68.0
0043: Accept: /
0050: Content-Length: 11
0064: Content-Type: application/x-www-form-urlencoded
0095:
=> Send data, 11 bytes (0xb)
0000: hello=world
== Info: upload completely sent off: 11 out of 11 bytes

2、curl 显示 boundary 数据

curl -F "hello=world" -F file=@/etc/timezone https://const.net.cn/test/ --trace-ascii /dev/stdout

输出结果：

0000: POST /test/ HTTP/1.1 0016: Host: const.net.cn 002a: User-Agent:
curl/7.68.0 0043: Accept: / 0050: Content-Length: 313 0065:
Content-Type: multipart/form-data; boundary=-------------------- 00a5:
----584e7b2299bf345b 00bb:
=> Send SSL data, 5 bytes (0x5) 0000: ....J
=> Send SSL data, 1 bytes (0x1) 0000: .
=> Send data, 313 bytes (0x139) 0000: --------------------------584e7b2299bf345b 002c: Content-Disposition: form-data; name="hello" 005a: 005c: world 0063:
--------------------------584e7b2299bf345b 008f: Content-Disposition: form-data; name="file"; filename="timezone" 00d1: Content-Type:
application/octet-stream 00f9: 00fb: Asia/Shanghai. 010b:
--------------------------584e7b2299bf345b--
== Info: We are completely uploaded and fine

１、查看curl与时间相关的选项

curl -h |grep time

有用的输出

--connect-timeout <seconds> Maximum time allowed for connection
--expect100-timeout <seconds> How long to wait for 100-continue
--keepalive-time <seconds> Interval time for keepalive probes
-m, --max-time <seconds> Maximum time allowed for the transfer
-y, --speed-time <seconds> Trigger 'speed-limit' abort after this time

2、控制连接超时--connect-timeout 5

curl -v --connect-timeout 1 https://const.net.cn

当出现连接超时时，会提示如下信息

curl: (28) Connection timed out after 1001 milliseconds

3、总超时时间--max-time
　我们希望curl程序在运行一段时间后，不管有没有执行完成都能正常退出。就用这个max-time

curl -v -m 60 https://const.net.cn

4、--speed-time　的用法
speed-time是用来根据速率来控制连接是否断开的。
用法：

curl -o const.log "https://const.net.cn" --speed-time 5 --speed-limit 1

是说将url内容保存到const.log中, 如果传输速度小于1字节/秒的状态持续5秒,该连接就会断开，并退出程序。

１、curl -w参数

curl -h |grep "write-out"

-w, --write-out <format> Use output FORMAT after completion

2、显示所有时间示例

curl -o /dev/null -s -w "time_namelookup:%{time_namelookup}\ntime_connect: %{time_connect}\ntime_starttransfer: %{time_starttransfer}\ntime_total: %{time_total}\n"  "https://const.net.cn/"

输出:

time_namelookup:0.058759
time_connect: 0.069912
time_starttransfer: 0.147355
time_total: 0.167685

3、参数说明

time_namelookup： DNS 服务器域名解析的时间（以上时间单位都是s）
time_connect： client 发出请求，到 c/s 建立TCP 的时间；里面包括 DNS 解析的时间
time_starttransfer： client 发出请求；到 server 响应发出第一个字节开始的时间；包括前面的2个时间
time_total： 从请求发起到链接关闭的总耗时

4、官方英文说明

time_appconnect:　The time, in seconds, it took from the start until the SSL/SSH/etc connect/handshake to the remote host was completed. (Added in 7.19.0)
time_connect: The time, in seconds, it took from the start until the TCP connect to the remote host (or proxy) was completed.
time_namelookup:　The time, in seconds, it took from the start until the name resolving was completed.
time_pretransfer:　The time, in seconds, it took from the start until the file transfer was just about to begin. This includes all pre-transfer commands and negotiations that　are specific to the particular protocol(s) involved.
time_redirect: The time, in seconds, it took for all redirection steps including name lookup, connect, pretransfer and transfer before the final transaction was started.　time_redirect shows the complete execution time for multiple redirections. (Added in 7.12.3)
time_starttransfer:　The time, in seconds, it took from the start until the first byte was just about to be transferred. This includes time_pretransfer and also the time the server needed to calculate the result.
time_total:　The total time, in seconds, that the full operation lasted.

5、格式可以使用字符串，格式化文件以及标准输入

The format can　be specified as a literal "string", or you can have　curl read the format from a file with "@filename" and to tell curl to read the format from stdin you write "@-".

6、使用格式文件示例

cat curl-format.txt

   time_namelookup:%{time_namelookup}\n
      time_connect:%{time_connect}\n
   time_appconnect:%{time_appconnect}\n
     time_redirect:%{time_redirect}\n    
  time_pretransfer:%{time_pretransfer}\n  
time_starttransfer:%{time_starttransfer}\n
------------------------------\n
        time_total:  %{time_total}\n

使用示例：

curl -o /dev/null -s -w "@curl-format.txt"  "https://const.net.cn/"

输出结果：

   time_namelookup:0.165160
      time_connect:0.240436
   time_appconnect:0.326137
     time_redirect:0.000000
  time_pretransfer:0.326211
time_starttransfer:0.412927
------------------------------
        time_total:  0.486244