backslash char alternatives on windows-CodePudding

On linux I can rappresent the / char in a different way:

${HOME:0:1}

So, for example, cat ${HOME:0:1}etc${HOME:0:1}passwd would be treated like cat /etc/passwd

Is there any way I can do the same thing on windows via powershell and cmd.exe for the backslash?

CodePudding user response：

PowerShell has no equivalent to the parameter expansions available in POSIX-compatible shells such as Bash, of which your substring extraction (${HOME:0:1} to get the substring of length 1 at character position 0, i.e the first char. of the value of variable $HOME) is an example (link is to the Bash manual).

However, PowerShell makes it easy:

to embed the results of arbitrary expressions and even whole statements inside expandable (double-quoted) string ("..."), using $(...), the subexpression operator.
to pass the results of any expression or command (pipeline) as an argument to a command, by enclosing it in (...), the grouping operator.

The following command variations are equivalent, and dynamically use the platform-appropriate path (directory) separator, i.e. / on Unix-like platforms, and \ on Windows:

# -> '/etc/passwd' on Unix
# -> '\etc\passwd' on Windows
Write-Output "$([System.IO.Path]::DirectorySeparatorChar)etc$([System.IO.Path]::DirectorySeparatorChar)passwd"

# Ditto.
Write-Output ('{0}etc{0}passwd' -f [System.IO.Path]::DirectorySeparatorChar)