jf22901
- 55
- 1
Hi all.
If I read in variables entered by the user, how can I check to make sure the correct number of variables were entered? For example, after reading in a data file and making it into an array, I have:
echo "To check the data, enter the first element number, last element number and step size as x y z:"
read x y z
It then goes on to start a loop, but what I would like now (before the loop) is a check to see if three variables have been entered, before the rest of the script continues. I've tried 'read $1 $2 $3' and 'read $x $y $z', but doing so results in echo "$#" = 0. I'm sure it's something simple, but I can't fathom it out. (In my defence, I did only learn bash scripting last week!)
I've attached a copy of the script as a text file in case the above makes no sense! The data file it reads is just a file of random numbers I am practising with.
Many thanks in advance!
If I read in variables entered by the user, how can I check to make sure the correct number of variables were entered? For example, after reading in a data file and making it into an array, I have:
echo "To check the data, enter the first element number, last element number and step size as x y z:"
read x y z
It then goes on to start a loop, but what I would like now (before the loop) is a check to see if three variables have been entered, before the rest of the script continues. I've tried 'read $1 $2 $3' and 'read $x $y $z', but doing so results in echo "$#" = 0. I'm sure it's something simple, but I can't fathom it out. (In my defence, I did only learn bash scripting last week!)
I've attached a copy of the script as a text file in case the above makes no sense! The data file it reads is just a file of random numbers I am practising with.
Many thanks in advance!