http://m.blog.csdn.net/blog/mayadong7349/7019208

使用curl在命令行中下载文件

linux下curl简单应用详解

http://blog.sina.com.cn/s/blog_4da051a60101drqv.html

(对curl命令的使用比较齐全)

http://blog.csdn.net/csfreebird/article/details/9237925

用curl访问HTTPS站点并登录

http://blog.csdn.net/sjin_1314/article/details/17392675

linux C libcurl https 使用

http://www.ichiayi.com/wiki/tech/curl_ssl

cURL 讀取雙向 ssl 認證 Web Server 網頁方式

CURL使用SSL证书访问HTTPS

http://blog.chinaunix.net/uid-192452-id-3954329.html

若服务端要求客户端认证，需要将pfx证书转换成pem格式

openssl pkcs12 -clcerts -nokeys -in cert.pfx -out client.pem #客户端个人证书的公钥

openssl pkcs12 -nocerts -nodes -in cert.pfx -out key.pem #客户端个人证书的私钥

也可以转换为公钥与私钥合二为一的文件

openssl pkcs12 -in cert.pfx -out all.pem -nodes #客户端公钥与私钥，一起存在all.pem中

执行curl命令

１、使用client.pem+key.pem

curl -k --cert client.pem --key key.pem https://www.xxxx.com

2、使用all.pem

curl -k --cert all.pem https://www.xxxx.com

使用-k，是不对服务器的证书进行检查，这样就不必关心服务器证书的导出问题了。

OpenSSL Verify return code: 20 (unable to get local issuer certificate)

http://stackoverflow.com/questions/11548336/openssl-verify-return-code-20-unable-to-get-local-issuer-certificate

yingc@yingc:~/work/public/solution$ openssl s_client -connect 74.125.128.139:443
CONNECTED(00000003)
depth=2 C = US, O = GeoTrust Inc., CN = GeoTrust Global CA
verify error:num=20:unable to get local issuer certificate
verify return:0
---
Certificate chain
0 s:/C=US/ST=California/L=Mountain View/O=Google Inc/CN=*.google.com
   i:/C=US/O=Google Inc/CN=Google Internet Authority G2
1 s:/C=US/O=Google Inc/CN=Google Internet Authority G2
   i:/C=US/O=GeoTrust Inc./CN=GeoTrust Global CA
2 s:/C=US/O=GeoTrust Inc./CN=GeoTrust Global CA
   i:/C=US/O=Equifax/OU=Equifax Secure Certificate Authority

SSL-Session:
    Protocol : TLSv1.1
    Cipher    : ECDHE-RSA-RC4-SHA
    Session-ID: 867D004577B0B77EA7ACE36EBEA8234C2BE21ABBEDA4A2B17CD9BEB9CA08E5F8
    Session-ID-ctx:
    Master-Key: 8C9F4C5E01512A14D6F062DE6BDF33F2032A85215C5449055D25D52151458B5380351D0C84D42215455320E4E2EC473D
    Key-Arg   : None
    PSK identity: None
    PSK identity hint: None
    SRP username: None
    TLS session ticket lifetime hint: 100800 (seconds)
    TLS session ticket:
    0000 - 17 25 ea c9 98 a9 1d bd-35 01 ce 18 a2 87 ec ea   .%......5.......
    0010 - 29 19 21 fc 79 a3 e4 23-89 97 f2 52 88 1d d1 0c   ).!.y..#...R....
    0020 - 2f 69 4c 20 78 9c e4 73-e2 8c 71 aa fa 83 67 84   /iL x..s..q...g.
    0030 - 56 8e 1d 3b 55 03 3b ad-b5 bb 6b df 85 d1 a6 af   V..;U.;...k.....
    0040 - 19 a5 38 41 4a f9 8a 19-52 11 bd 68 e3 5b 47 15   ..8AJ...R..h.[G.
    0050 - 3a 84 52 af a4 81 db 90-82 db f2 9d 47 df 00 6f   :.R.........G..o
    0060 - c5 28 c4 ef 85 94 f0 72-fc 47 7f 38 4f 1f 48 3e   .(.....r.G.8O.H>
    0070 - 37 ba e1 0e 5c c6 62 05-62 8c 35 27 73 74 73 92   7...\.b.b.5'sts.
    0080 - 7a c1 a2 10 12 db b7 be-37 04 8a 56 f3 d1 58 75   z.......7..V..Xu
    0090 - df a3 ef 31                                       ...1

Start Time: 1388745557
Timeout : 300 (sec)
Verify return code: 20 (unable to get local issuer certificate)

openssl s_client -CApath /etc/ssl/certs/ -connect 74.125.128.139:443

Expansion: NONE
SSL-Session:
    Protocol : TLSv1.1
    Cipher    : ECDHE-RSA-RC4-SHA
    Session-ID: 932BBA8E505C788ABD841F8FA94E685654264E1076A723C3AF8C6967744A1936
    Session-ID-ctx:
    Master-Key: A2BA6685C97FFD38906103B6AC7CC01BE017AC4D890D41E8167B5063EA9797C6395F3E01437754B7D9FF7726156C9F55
    Key-Arg   : None
    PSK identity: None
    PSK identity hint: None
    SRP username: None
    TLS session ticket lifetime hint: 100800 (seconds)
    TLS session ticket:
    0000 - 17 25 ea c9 98 a9 1d bd-35 01 ce 18 a2 87 ec ea   .%......5.......
    0010 - 5d 6c 40 86 a9 e1 04 35-17 0c 06 ab 8d e1 9c aa   ]l@....5........
    0020 - 24 4c 13 af a0 6b fe e3-aa bf b0 38 64 67 5e 78   $L...k.....8dg^x
    0030 - aa f2 08 b2 74 06 ce 16-21 ab 53 e2 5b 22 3b 41   ....t...!.S.[";A
    0040 - 82 dc 11 d3 a5 1c 72 d9-17 11 f8 cc 3b 42 a7 91   ......r.....;B..
    0050 - 6d d2 0d 11 2a 0d 8b 25-50 5c e5 65 7a e8 44 d2   m...*..%P\.ez.D.
    0060 - 22 94 21 5b 8d dc b6 91-ba ee 09 95 f0 6b 75 1b   ".![.........ku.
    0070 - 90 bf 19 55 32 21 90 c4-70 c1 76 15 15 cb 9a 43   ...U2!..p.v....C
    0080 - e8 00 16 77 10 fc 7c a3-d6 8f 73 37 c9 2e b4 0e   ...w..|...s7....
    0090 - 07 d5 1d 90                                       ....

Start Time: 1388745845
Timeout : 300 (sec)
Verify return code: 0 (ok)

Curl和Wget访问HTTPS连接出现Unable to establish SSl connection错误

wget 使用 –no-check-certificate 参数
curl 使用 -k或者--insecure 参数

./curl -o aa.js https://s.ytimg.com/yts/jsbin/html5player-vf
lG49soT.js --cacert /dvb/ca-certificates.crt

、

curl: (60) SSL certificate problem, verify that the CA cert is:
error:14090086:SSL routines:SSL3_GET_SERVER_CERTIFICATE:certificate verify failed
More details here: http://curl.haxx.se/docs/sslcerts.html

curl performs SSL certificate verification by default, using a "bundle"
of Certificate Authority (CA) public keys (CA certs). If the default
bundle file isn't adequate, you can specify an alternate file
using the --cacert option.
If this HTTPS server uses a certificate signed by a CA represented in
the bundle, the certificate verification probably failed due to a
problem with the certificate (it might be expired, or the name might
not match the domain name in the URL).
If you'd like to turn off curl's verification of the certificate, use
the -k (or --insecure) option.

curl： curl是利用URL语法在命令行方式下工作的文件传输工具。 [百科： http://baike.baidu.com/view/1326315.htm]
官网： http://curl.haxx.se/
其中libcurl有C语言、Python接口（PyCurl： http://pycurl.sourceforge.net/）等等。 curl.exe也可以作为一个命令行下载工具。

将来学习了多线程，可以改为多线程下载。

最简单的下载语法：

curl -o [filename] <url>

例如：

Microsoft Windows [版本 6.0.6001]

版权所有 (C) 2006 Microsoft Corporation。保留所有权利。

C:\Windows\system32>curl -o E:\MIT_BIH_Arrhythmia_Database\103.dat  http://physionet.org/physiobank/database/mitdb/103.dat

  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current

                                 Dload  Upload   Total   Spent    Left  Speed

  1 1904k    1 23082    0     0   3582      0  0:09:04  0:00:06  0:08:58  3556

这样子就从网页http://physionet.org/physiobank/database/mitdb/103.dat把文件103.dat下载到本地E盘E:\MIT_BIH_Arrhythmia_Database\103.dat

curl --head <url>

获取下载文件的大小。例如：

C:\Windows\system32>curl --head http://physionet.org/physiobank/database/mitdb/100.atr

HTTP/1.1 200 OK

Date: Mon, 28 Nov 2011 05:35:46 GMT

Server: Apache/2.2.17 (Fedora)

Last-Modified: Thu, 30 Jul 1992 01:21:18 GMT

ETag: "82c1c18-11ce-287fa5a2e9f80"

Accept-Ranges: bytes

Content-Length: 4558

Connection: close

Content-Type: application/octet-stream

curl --connect-timeout <seconds> <url>

（参考： http://blog.csdn.net/learnhard/article/details/5683703）

连接超时时间设置。

curl -m <seconds> <url>

传输数据超时时间设置。例如：

C:\Windows\system32>curl -o E:\MIT_BIH_Arrhythmia_Database\104.dat  -m 20 "http://physionet.org/physiobank/database/mitdb/104.dat"

  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current

                                 Dload  Upload   Total   Spent    Left  Speed

  1 1904k    1 20162    0     0    953      0  0:34:06  0:00:21  0:33:45   377

curl: (28) Operation timed out after 20000 milliseconds with 20162 out of 195000

0 bytes received

# !/usr/bin/env python

# Filename: down.py

# download files from http://physionet.org/physiobank/database/mitdb/

import os

home = r"E:\MIT_BIH_Arrhythmia_Database"

fext = [".atr", ".dat", ".hea"]

hurl = r"http://physionet.org/physiobank/database/mitdb/"

for ext in fext:

    for index in range(100, 234):

        fname  = str(index) + ext

        fsave  = home + os.path.sep + fname

        fget   = hurl + fname

        if False == os.path.isfile(fsave):

            command = "curl -o " + fsave + " " + fget

            os.system(command)