我在我$PATH
想要编辑的文件中有一个指向脚本的符号链接。我忘记了文件路径,所以我尝试执行以下操作:
$ which my_script_link | readlink
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我希望输出文件路径,但它输出
> readlink: missing operand
> Try 'readlink --help' for more information
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我之前在其他情况下也看到过类似的行为(比如尝试将文件列表通过管道传输到 vim 中进行编辑)。我知道有一些解决方法,比如 subshell readlink $(which my_script_link)
,但我想了解为什么管道在这种情况下不能像我认为的那样工作。
谢谢!
我在用 gpg2 解密文件时遇到问题。我最初使用 gpg 1.4 版加密文件。我现在使用的机器有 gpg (1.4) 和 gpg2。用 gpg 解密工作得很好,但是当我用 gpg2 执行相同的命令时,它超时了:
$ echo "This is a test" > test.txt
$ gpg -r MyOwnId --encrypt test.txt
(creates test.txt.gpg)
$ gpg --decrypt test.txt.gpg
(provide passphrase for MyOwnId)
-> This is a test
$ gpg2 --decrypt test.txt.gpg
(after a long timeout)
-> gpg: encrypted with 2048-bit RSA key, ID #######, created YYYY-MM-DD "MyOwnId"
gpg: public key decryption failed: Timeout
gpg: decryption failed: No secret key
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这是怎么回事?它说“没有密钥”,但运行 gpg2 --list-secret-keys 显示:
/home/me/.gnupg/pubring.kbx …
Run Code Online (Sandbox Code Playgroud) 我有一种情况,我有几行,我需要每行都有两个不同的字段。具体来说,我在参考书目中有一个参考列表,我想获得姓氏和年份。
样本输入:
Aloise-Young, P.A. (1993). The development of self-presentation. Self-promotion in 6- to 10-year-old children. Social Cognition, 11, 201-222.
Banerjee, R. (2002). Children's understanding of self-presentational behavior: Links with mental-state reasoning and the attribution of embarrassment. Merril-Palmer Quarterly, 48, 378-404.
Bennett, M., & Wellman, H. (1989). The role of second-order belief-understanding and social context in children's self-attribution of social emotions. Social Development, 9, 126-130.
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期望的输出:
Aloise-Young 1993
Banerjee 2002
Bennett 1989
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我可以得到姓氏 cat file | cut -d, -f1
我可以得到岁月 cat …