我正在使用curl命令来获取网页。但有时它不会给出响应输出。我的卷曲命令是
[root@panzhengyu ~]# curl https://nn.cbcb.us/register.php
[root@panzhengyu ~]# curl https://nn.cbcb.us/register.php
[root@panzhengyu ~]# curl https://nn.cbcb.us/register.php
[root@panzhengyu ~]# curl https://nn.cbcb.us/register.php
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gbk">
<title>²ށ^ - t66y.com</title>
<meta name="keywords" content="²ށ24,²ށ^,1024app,²ށ𠯰,С²ܡpp,מo´a,מԐ´a,WĀo´a,Ԃþo´a,݄؎½»·,¼¼ϧӑՓ^,ޟȷ µņ쏃,тr´,³ʈ̎ČW,՚¾³ʈ̓°Ժ,httpЂܤ,²ށD,²ށ,t66y.com" />
<meta name="description" content="²ށ^ t66y.com" />
<base href="https://nn.cbcb.us/" />
<link rel="stylesheet" href="//www.viidii.info/web/style.css?v=2.0253" type="text/css" />
</head><body>
<div id="header">
<div class="banner" style="padding-left:5px;"><a href="../../../"><FONT SIZE="7" COLOR="white"><B>²ށ^</B></FONT></a></div>
<div class="h guide" colspan="2">»
我已经尝试了四次。但是前三次没有输出。我不知道为什么会这样？ 我的卷曲版本是
[root@panzhengyu ~]# curl --version
curl 7.61.1 (x86_64-redhat-linux-gnu) libcurl/7.61.1 OpenSSL/1.0.1e zlib/1.2.3 c-ares/1.14.0 libssh2/1.8.0 nghttp2/1.6.0
Release-Date: 2018-09-05
Protocols: dict file ftp ftps gopher http https imap imaps ldap ldaps pop3 pop3s rtsp scp sftp smb smbs smtp smtps telnet tftp
Features: AsynchDNS IPv6 Largefile GSS-API Kerberos SPNEGO NTLM NTLM_WB SSL libz HTTP2 UnixSockets HTTPS-proxy Metalink
[root@panzhengyu ~]#
以下是 "curl -v https://nn.cbcb.us/register.php" 的日志，直接输出到 stderr。
curl -v https://nn.cbcb.us/register.php
* Trying 2606:4700:30::681b:b329...
* TCP_NODELAY set
* Connected to nn.cbcb.us (2606:4700:30::681b:b329) port 443 (#0)
* Cipher selection: ALL:!EXPORT:!EXPORT40:!EXPORT56:!aNULL:!LOW:!RC4:@STRENGTH
* successfully set certificate verify locations:
* CAfile: /etc/pki/tls/certs/ca-bundle.crt
CApath: none
* TLSv1.2 (OUT), TLS handshake, Client hello (1):
* TLSv1.2 (IN), TLS handshake, Server hello (2):
* NPN, negotiated HTTP2 (h2)
* TLSv1.2 (IN), TLS handshake, Certificate (11):
* TLSv1.2 (IN), TLS handshake, Server key exchange (12):
* TLSv1.2 (IN), TLS handshake, Server finished (14):
* TLSv1.2 (OUT), TLS handshake, Client key exchange (16):
* TLSv1.2 (OUT), TLS change cipher, Change cipher spec (1):
* TLSv1.2 (OUT), TLS handshake, Next protocol (67):
* TLSv1.2 (OUT), TLS handshake, Finished (20):
* TLSv1.2 (IN), TLS change cipher, Change cipher spec (1):
* TLSv1.2 (IN), TLS handshake, Finished (20):
* SSL connection using TLSv1.2 / ECDHE-ECDSA-AES128-GCM-SHA256
* Server certificate:
* subject: OU=Domain Control Validated; OU=PositiveSSL Multi-Domain; CN=sni133140.cloudflaressl.com
* start date: Jun 8 00:00:00 2018 GMT
* expire date: Dec 15 23:59:59 2018 GMT
* subjectAltName: host "nn.cbcb.us" matched cert's "*.cbcb.us"
* issuer: C=GB; ST=Greater Manchester; L=Salford; O=COMODO CA Limited; CN=COMODO ECC Domain Validation Secure Server CA 2
* SSL certificate verify ok.
* Using HTTP2, server supports multi-use
* Connection state changed (HTTP/2 confirmed)
* Copying HTTP/2 data in stream buffer to connection buffer after upgrade: len=0
* Using Stream ID: 1 (easy handle 0xf110e0)
> GET /register.php HTTP/2^M
> Host: nn.cbcb.us^M
> User-Agent: curl/7.61.1^M
> Accept: */*^M
> ^M
* Connection state changed (MAX_CONCURRENT_STREAMS == 256)!
< HTTP/2 200 ^M
< date: Tue, 23 Oct 2018 06:05:30 GMT^M
< content-type: text/html^M
< set-cookie: __cfduid=d324f19ad0265d40a531c2d0fee4b8ff61540274730; expires=Wed, 23-Oct-19 06:05:30 GMT; path=/; domain=.cbcb.us; HttpOnly; Secure^M
< x-powered-by: PHP/5.6.33^M
< vary: Accept-Encoding^M
< expect-ct: max-age=604800, report-uri="https://report-uri.cloudflare.com/cdn-cgi/beacon/expect-ct"^M
< server: cloudflare^M
< cf-ray: 46e20329f9c478e6-LAX^M
< ^M
* Connection #0 to host nn.cbcb.us left intact
试试这个来检查 Curl 的日志。您将获得更多信息： 这是命令
curl -v 'https://nn.cbcb.us/register.php'>> test.logs
资料来源：https://www.unix.com/shell-programming-and-scripting/252609-curl-v-logs.html