有人可以解释为什么我不能将 cut 命令存储在变量中吗?
user:~$ echo "foo bii doo" | cut -d ' ' -f 2
bii # as expected
# now put cut command into a variable:
user:~$ c="cut -d ' ' -f 2"
user:~$ echo "foo bii doo" | $c
cut: "'": No such file or directory
user:~$ c="cut -d \ -f 2"
user:~$ echo "foo bii doo" | $c
foo bii doo
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这不是一般的引用问题,因为 tr 有效:
user:~$ t="tr -d 'oo'"
user:~$ echo "foo bii doo" | $t
f bii …
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