It appears to be common to split on ; and your program is no exception.

It doesn't appear to handle quoted path names, which are valid, both the "pa;th" and "pa th"\"of space" variety

shell commands (copy paste into cmd.exe):

md "pa;th"
echo @echo how the pa;th are ya  > "pa;th"\pathme.bat
pathme
set path="pa;th";%path%
pathme
md "pa;th"\"of space"
echo @echo how the pa;th\of space are ya  > "pa;th\of space"\pathem.ba
+t
pathem
set path="pa;th"\"of space";%path%
pathem
[download]

Output:

C:\>md "pa;th"

C:\>echo @echo how the pa;th are ya  > "pa;th"\pathme.bat

C:\>pathme
'pathme' is not recognized as an internal or external command,
operable program or batch file.

C:\>set path="pa;th";%path%

C:\>pathme
how the pa;th are ya

C:\>md "pa;th"\"of space"

C:\>echo @echo how the pa;th\of space are ya  > "pa;th\of space"\pathe
+m.bat

C:\>pathem
'pathem' is not recognized as an internal or external command,
operable program or batch file.

C:\>set path="pa;th"\"of space";%path%

C:\>pathem
how the pa;th\of space are ya

C:\>
[download]