In my script I wrote down this control expression:
if ! [[ $start -gt $(cut -f3 rooms.txt) -a $end -gt $(cut -f4 rooms.txt) ]]; then
echo "Invalid prenotation";
./prenote.sh;
fi
start and end are simple numbers. Each record in file rooms.txt is built in this way:
room;date;start;end;username
There are non blank spaces in the record. When I run the script I get a syntax error near the if statement.
Can someone tell me where the error is? Thanks
The operator -a for "and" is not valid in [[...]] conditionals. Use && instead.
But if you're doing numeric comparisons in bash, it might make more sense to use ((...)) instead of [[...]]. Then the normal relational operators are numeric instead of string-based, so you can use > instead of -gt:
if ! (( start > $(cut -f3 rooms.txt) && end > $(cut -f4 rooms.txt) )); then
...
fi
However, this approach only works if rooms.txt has only one line; otherwise, you'll get syntax errors when the $(cut...) commands produce more than one number. I'm not sure exactly what problem you're solving, but an approach something like this might be fruitful:
while read _ _ low high _; do
if ! (( start > low && end > high )); then
...
fi
done <rooms.txt
[[-a filenameis true if the file exists. So-ahas a different meaning inside[(test) and[[. By the way, you don't need a semi-colon at the end of every line.