Probably a quick and easy one for you guys but I can't actually find an answer anywhere.
What does this mean? Break it down for me, please?
The naswer is simple:
[aDt]
: the character a
or D
or t
. *
: zero or more (any) characters. .
: the dot. t
: the t
character. ?
: any (single) character. t
: the t
character. "[aDt]*.t?t" is an expression of the "shell expansion" (there are several types, this one is "pattern matching").
This expansions use wildcard-type items to match not only a single name, but multiple.
In the case of ls command (your question, but the same applies to any command), it will list all the files having a matching name, but not other files.
[aDt] matches any of the character "a", "D", "t"
* matches any number (even zero) of any character
? matches any single character
This expression can match, for example
D-data.txt
a-what.tNt
t.tst
but not
mega.txt (first letter is not a, D or t)
ciao.TXT (the uppercase T of TXT do not match)
ciaotxt (does not contain a dot)
This is only a partial reply, things are much more complicated.
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