How to properly execute this while loop in bash?

Question

#!/bin/bash

f=1
c=$1
while [[ $c != 0 ]]
do
        $f=$(($c*$f))
        $c=$(($c-1))
done
echo $c

I keep getting the error

./process.sh: line 8: 1=0: command not found
./process.sh: line 7: 5=5: command not found

When running ./process.sh 5

Your loop starts with c=1 and then runs while c!=0 and it subtracts 1 from c each time? That's not much of a loop. — FatalError
– FatalError, Commented Mar 10, 2013 at 0:37

Andrew White · Accepted Answer · 2013-03-10 00:36:06Z

5

The $ means "value of" so $f gets evaluated to the string literal 1. So...

    $f=$(($c*$f))
    $c=$(($c-1))

should be

    f=$(($c*$f))
    c=$(($c-1))

answered Mar 10, 2013 at 0:36

Andrew White

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Comments

zzk · Accepted Answer · 2013-03-10 00:36:04Z

1

in the loop, it should be

f=$(($c*$f))
c=$(($c-1))

answered Mar 10, 2013 at 0:36

zzk

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