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Explore Stack Internal The two are not equivalent. In a line that contains $(foo), the $(foo) is replaced with the output of the command foo. For example:
$ echo "hello $(echo world)" hello world In a line that contains $foo, the $foo is replaced with the value of the environment variable named foo. For example:
$ foo=world $ echo "hello $foo" hello world The two are not equivalent. In a line that contains $(foo), the $(foo) is replaced with the output of the command foo. For example:
$ echo "hello $(echo world)" hello world In a line that contains $foo, the $foo is replaced with the value of the environment variable named foo. For example:
$ foo=world $ echo "hello $foo" hello world The two are not equivalent. In a line that contains $(foo), the $(foo) is replaced with the output of the command foo. For example:
$ echo "hello $(echo world)" hello world In a line that contains $foo, the $foo is replaced with the value of the variable named foo. For example:
$ foo=world $ echo "hello $foo" hello world The two are not equivalent. In a line that contains $(foo), the $(foo) is replaced with the output of the command foo. For example:
$ echo "hello $(echo world)" hello world In a line that contains $foo, the $foo is replaced with the value of the environment variable named foo. For example:
$ foo=world $ echo "hello $foo" hello world