Windows PATH to posix path conversion in bash

Question

How can I convert a Windows dir path (say c:/libs/Qt-static) to the correct POSIX dir path (/c/libs/Qt-static) by

Answer 1

Here is my implementation (tested on git bash).

From POSIX to Windows

sed '
    \,/$, !s,$,/,
    \,^/, s,/,:/,2
    s,^/,,
    s,/,\\,g
    ' <<< "$@"

Works for:

/c/git
relative/dir
c:/git
~
.
..
/c
/c/
./relative/dir
/sd0/some/dir/

except

/

Explanation:

\,^/, s,/,:/,2 (converts /drive/dir/ to /drive:/dir/) is the heart of it and inserts : before the 2nd /. I use , for delim instead of / for readability. If starting with / (\,^/,), then replace / with :/ for the 2nd occurrence. I do not want to assume drive letter length of 1 so this works for /sd0/some/dir.

s,^/,, removes the leading / and s,/,\\,g converts all / to \.

\,/$, !s,$,/, is to handle the corner case of /c and ensure 2nd / (/c/) for the next command to work.

Note:

If here string <<< does not work in your shell then you can echo and pipe as

echo "$@" | sed ...

Errata

Here e script