Centos 6. 最近更新了ca-certificates后遇到了一些麻烦。我有最新版本的针对 centos 6 的 curl：
-bash-4.1$ curl -V -v
curl 7.19.7 (x86_64-redhat-linux-gnu) libcurl/7.19.7 NSS/3.27.1 zlib/1.2.3 libidn/1.18 libssh2/1.4.2
Protocols: tftp ftp telnet dict ldap ldaps http file https ftps scp sftp
Features: GSS-Negotiate IDN IPv6 Largefile NTLM SSL libz
和 wget：
-bash-4.1$ wget -V -v
GNU Wget 1.12 built on linux-gnu.
+digest +ipv6 +nls +ntlm +opie +md5/openssl +https -gnutls +openssl
-iri
Wgetrc:
/etc/wgetrc (system)
Locale: /usr/share/locale
Compile: gcc -DHAVE_CONFIG_H -DSYSTEM_WGETRC="/etc/wgetrc"
-DLOCALEDIR="/usr/share/locale" -I. -I../lib -O2 -g -pipe -Wall
-Wp,-D_FORTIFY_SOURCE=2 -fexceptions …