问题
Initiated by the reply.
- How can I use only Regex instead of wildcards?
- Where do you really need wildcards and globbing if you can use Regex?
- Have Regexes evolved from wildcards or vice versa?
回答1:
I think your confusion is based on the differences between shell-globbing wildcards (the * character) and the regular expression symbol (the * character). Regexes are not shell-globbing, they are a lot more powerful and useful, but for everyday shell use, wildcards and shell-globbing are "good enough."
- How can I use only Regex instead of wildcards?
Don't use the shell. Write a Perl/Python/Ruby/[your-choice-of-scripting-language-here] script to do the job for you. It'll probably be faster, since it won't have to fork so much.
- Where do you really need wildcards and globbing if you can use Regex?
No. But in most shells, you don't have regexes, so you have globs. Think of them as a poor-man's regex.
- Have Regexes evolved from wildcards or vice versa?
Regexes came from set theory, and specifically early text editors (one early Unix text editor called ed had a regex-like feature, which was then re-used in a little program called grep, which you might have heard of). I imagine wildcards have just been features of the shell. They can't be hard to implement, so shell writers would add them fairly quickly, and with little overhead.
回答2:
Described in the man page:
-name pattern
True if the last component of the pathname being examined matches pattern. Special shell pattern matching characters (
[,],*, and?) may be used as part of pattern. These characters may be matched explicitly by escaping them with a backslash (\).
So in other words, patterns that are usable in shell glob patterns are usable by find.
Man pages can generally tell you a lot. ;)
$ man find
for more information.
回答3:
My initial question had a wrong premise; they are wildcards, not regexes! Glob-program handles wildcards.
Regular expressions
Note that wildcard patterns are not regular expressions, although they are a bit similar. First of all, they match filenames, rather than text, and secondly, the conventions are not the same: for example, in a regular expression '*' means zero or more copies of the preceding thing. Now that regular expressions have bracket expressions where the negation is indicated by a '^', POSIX has declared the effect of a wildcard pattern "[^...]" to be undefined.
The explanation is not 100% thorough. For example, you can easily match filenames with Regex.
来源：https://stackoverflow.com/questions/1323805/confusion-with-shell-globbing-wildcards-and-regex