Increment a variable in unix bash


 
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# 8  
Old 04-24-2012
Radulov,

actually, its not throwing an error at the command you just listed. So it is bash.

-A
# 9  
Old 04-24-2012
OK,
so it's not the (( arithmetic expression )) construct that throws the error Smilie
# 10  
Old 04-24-2012
Radulov,

Can you suggest how i could incorporate (( c += 1 )) in my bash shell script and echo the value of $c?

-A
# 11  
Old 04-24-2012
Code:
for i in *.*; do
  (( s += 1 ))
  printf '%d\n' $s
  j=$i$j
  mv -- "$i" "$j" 
done

# 12  
Old 04-24-2012
I tried to run a script:
Code:
#!/bin/bash
num=0
i=0
for i in {1..10}
do
(( num += 1 ))
echo $num
done

I get an error: num not found and the value of num is not incremented.

Could you please tweek the problem in this script?

-A
# 13  
Old 04-24-2012
Your script works for me ...

Code:
$ cat s
#!/bin/bash
num=0
i=0
for i in {1..10}
do
(( num += 1 ))
echo $num
done
$ chmod u+x s
$ ./s
1
2
3
4
5
6
7
8
9
10

# 14  
Old 04-24-2012
Are you editing these scripts in Microsoft Notepad, or some such? That will cause many strange errors by filling the file with carriage returns...
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