Shell Programming and Scripting

Here's what I have....

Code:

echo "Please enter four numbers: \c"
read max
for i in 1 2 3 4
do
read number
[ $number -gt $max ] && max=$number
done
echo "The maximum is: $max"

When I run it, for example, I type 1 2 3 4 and it does nothing...

this would require you hit enter between each number. also, please don't start a new thread for the same thing.

This looks like schoolwork, so I'll just give you some generic pointers for how to finish it.

1) There is a separate forum for schoolwork. Please put future posts in that forum.

2) RTFM. Type man bash or man ksh to learn the syntax of your shell. There is a ton of help in those manuals.

3) When you have no idea where a script is failing, put echo commands between every line so you can tell where it stops.

Code:

echo "Please enter four numbers: \c" 
read max
echo "1"
for i in 1 2 3 4 do
echo "2"

etc.

It is actually a project for work. I am using it to find a data file with the highest values, so I altered it here a little to just find the maximum number. How can I adjust it to read each number separated by spaces instead of hitting enter after each number?

You should have started off asking that, rather than asking us to fix a specific syntax error, then.

You've just 1 line of many numbers? Give us more details on the actual input file, pasting a sample of it if you could, and the desired output. I'd say awk is better suited than the shell for such a task though. Say you've a file of just numbers:

Code:

awk '{for (i=1;i<=NF;i++) if (0+$i > max) max=0+$i}END{print "max: " max}' file

Should show the highest number in that file. It scans every line and every word. It assumes the max will be greater than 0 though, since it's not initialized.

This is what I have..

Code:

echo "Please enter four numbers: \c"
read max
for i in 1 2 3
do
read number
[ $number -gt $max ] && max=$number
done
echo "The maximum is: $max"

How would I embed the sample you provided into the above?

That line replaces the whole script. I'm still confused as to what you want to do. Do you want to read from the keyboard or a file? Does the file only have 4 numbers in it on 1 line?