我正在fedora 23 中学习wget 实用程序。在多次使用wget 时，我收到相同的错误。例如，我测试的命令之一是：
wget ‐‐output-file=logfile.txt ‐‐recursive ‐‐spider http://www.howtogeek.com/
但我明白了：
idn_encode failed (3): ‘Non-digit/letter/hyphen in input’
--2016-06-17 16:40:09-- http://%E2%80%90%E2%80%90output-file=logfile.txt/
Resolving ‐‐output-file=logfile.txt (‐‐output-file=logfile.txt)... failed: No address associated with hostname.
wget: unable to resolve host address ‘‐‐output-file=logfile.txt’
idn_encode failed (3): ‘Non-digit/letter/hyphen in input’
--2016-06-17 16:40:10-- http://%E2%80%90%E2%80%90output-file=logfile.txt/
Resolving ‐‐output-file=logfile.txt (‐‐output-file=logfile.txt)... failed: No address associated with hostname.
wget: unable to resolve host address ‘‐‐output-file=logfile.txt’
--2016-06-17 16:40:11-- http://xn--recursive-u79da/
Resolving ‐‐recursive (xn--recursive-u79da)... failed: No address associated with hostname.
wget: unable to resolve host address ‘xn--recursive-u79da’
--2016-06-17 16:40:17-- http://xn--recursive-u79da/
Resolving ‐‐recursive (xn--recursive-u79da)... failed: No address associated with hostname.
wget: unable to resolve host address ‘xn--recursive-u79da’
--2016-06-17 16:40:18-- http://xn--spider-9f0ca/
Resolving ‐‐spider (xn--spider-9f0ca)... failed: No address associated with hostname.
wget: unable to resolve host address ‘xn--spider-9f0ca’
--2016-06-17 16:40:18-- http://xn--spider-9f0ca/
Resolving ‐‐spider (xn--spider-9f0ca)... failed: No address associated with hostname.
wget: unable to resolve host address ‘xn--spider-9f0ca’
--2016-06-17 16:40:29-- http://www.howtogeek.com/