Replace file name within unix script

[confuseddddd]

Have file where month is part of file name, example:AAA06BBB.TXT and want to be able to change the month (in this case from 06 to 07), each month within the script, not changing filename each month manually.
Currently, some one physically changes the file
name and I want to have the script change the file name.

Any suggestions?????

 

[Salem]

# rename a filename
new=`echo $old | awk '{
  a=substr($1,0,3)
  b=substr($1,4,2)
  c=substr($1,6);
  printf("%s%02d%s\n",a,(b+1)%12,c)}'`
mv $old $new

The

(b+1)%12

part wraps December round to January, but the precise form depends on whether months are numbered 00 to 11, or 01 to 12.

 

[confuseddddd]

Tried to execute the awk command but I am receiving errors...
rename[2]: old: not found.

And new is printing 01

Here is the script....can you see what I did wrong???

Thanks.


# rename a filename
old = AAA05BBB.TXT
print $old
new=`echo $old | awk '{
a=substr($1,0,3)
b=substr($1,4,2)
c=substr($1,6);
printf("%s%02d%s\n",a,(b+1)%12,c)}'`

print $new
#mv $old $new

 

[Salem]

Watch the spaces and quotes

$ old='AAA05BBB.TXT'
$ echo $old
AAA05BBB.TXT

 

[confuseddddd]

Tried it the way indicated and still receiving errors:

# rename a filename
$ old = 'AAA05BBB.TXT'
$ echo $old
new=`echo $old | awk '{
a=substr($1,0,3)
b=substr($1,4,2)
c=substr($1,6);
printf("%s%02d%s\n",a,(b+1)%12,c)}'`

echo $new
#mv $old $new


RESULTS:
rename[2]: $: not found.
rename[3]: $: not found.
01


Then tried another way:
old='AAA05BBB.TXT'
echo $old
new=`echo $old | awk '{
a=substr($1,0,3)
b=substr($1,4,2)
c=substr($1,6);
printf("%s%02d%s\n",a,(b+1)%12,c)}'`

echo $new
#mv $old $new


And received the results I expected:
AAA05BBB.TXT
AAA06BBB.TXT