execute cygwin sort command from batch file -

i trying run sort command batch file take lines new.txt , output them unique.txt

c:\cygwin64\bin\bash -c "sort -u new.txt > unique.txt"

this not working

however, if place new.txt home/administrator directory , run command in terminal works fine.

wrote script:

#!/bin/bash  sort -u /home/administrator/new.txt > unique.txt 

batch file:

set path=c:\cygwin64\bin;%path% c:\cygwin64\bin\bash.exe /usr/bin/u.sh 

all :)