perl -MTime::Piece -le '$m=localtime->tzoffset->minutes; printf "%+02.2d%02.2d\n", int($m/60), $m%60'
+1000

# cmd.exe friendly
perl -MTime::Piece -le "$m=localtime->tzoffset->minutes; printf qq(%+02.2d%02.2d\n), int($m/60), $m%60"
+1000