为什么这个4行bash脚本不起作用？

Question

基于这个答案：https://stackoverflow.com/a/4141042/226473

我想出了这个脚本：

ALT02884% for i in {0..4}
do
  printf "Set for $1" > "$i_directories"
done

但它会导致以下结果：

zsh: no such file or directory:
zsh: no such file or directory:
zsh: no such file or directory:
zsh: no such file or directory:
zsh: no such file or directory:

Answer 1

shell认为下划线是变量名的一部分。使用大括号告诉它查找名为i而不是i_directories的变量。

for i in {0..4}
do
  printf "Set for $1" > "${i}_directories"
done