bash 如何检查 RPM .spec 文件中是否存在文件？
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How to check if a file exists in an RPM .spec file?
提问by John
I have a spec file that needs to check if an older version of a file exists and if so delete it. For some reason, it is running the delete command regardless of whether the file exists and printing a "no such file or directory" error, which leads me to believe my if statement checking if the file exists is at fault. Here is my code.
我有一个规范文件，需要检查文件的旧版本是否存在，如果存在则将其删除。出于某种原因，无论文件是否存在，它都会运行删除命令并打印“没有这样的文件或目录”错误，这让我相信我的 if 语句检查文件是否存在是有问题的。这是我的代码。
if [ -e "/foo/bar/file.zip" ]; then
rm -rf /foo/bar/file.zip
fi
Any help is appreciated.
任何帮助表示赞赏。
回答by Etan Reisner
That rm -rfcommand cannotbe the source of that error message because -ftells rmto never fail (and to never print such error messages, try it locally rm -f /this/is/some/path/that/does/not/exist; echo $?). (This means, of course, that the test for file existence itself is unnecessary since rm -fdoes not care.
该rm -rf命令不能成为该错误消息的来源，因为它-f告诉rm永远不要失败（并且永远不要打印此类错误消息，请在本地尝试rm -f /this/is/some/path/that/does/not/exist; echo $?）。（当然，这意味着文件存在本身的测试是不必要的，因为rm -f它不在乎。
Additionally you do not need the -rflag if you are deleting a file (and it is safer not to include it (or -f) when you do not need them.
此外，-r如果您要删除文件，则不需要该标志（并且-f在不需要它们时不包含它（或）更安全。
So something else must be printing that message. Do you use that file anywhere else? Does anything from the old package's %preunuse it perhaps?
因此，必须有其他东西在打印该消息。你在其他地方使用那个文件吗？旧包中的任何东西都可以%preun使用它吗？
回答by Darshan Patel
[ -f /foo/bar/file.zip ] && rm -f /foo/bar/file.zip || echo "File Not Found"
回答by konsolebox
It's possible that you didn't add a space between the file path and -e:
您可能没有在文件路径和 之间添加空格-e：
if [ -e"/foo/bar/file.zip" ]; then
rm -rf /foo/bar/file.zip
fi
It would be synonymous to this which is always true:
这将是这个永远正确的同义词：
if [ -n "-e/foo/bar/file.zip" ]; then
rm -rf /foo/bar/file.zip
fi
