How can I resolve the "unary operator expected" error in the script?

Question

expr: syntax error
h2.sh: line 13: [: -gt: unary operator expected

#!/bin/sh


FILE=merchant.xml

OLDTIME=3600

CURTIME=$date
FILETIME=($date -r File)
TIMEDIFF=$(expr $CURTIME - $FILETIME)


if ["$TIMEDIFF" -gt "$OLDTIME" ]; then
   echo "File is older, do stuff here" | mail -s "hello" hardik.pahwa@guemstiger.de
fi

Answer 1

please add space here

if ["$TIMEDIFF" -gt "$OLDTIME" ]; then
    ^

It should be like

if [ "$TIMEDIFF" -gt "$OLDTIME" ]; then