Shell Programming and Scripting

zsh 4.3.4% cat file
ACFCFACCACARCSHFARCVJVASTVAJFTVAJVGHBAJ
zsh 4.3.4% cat file1
A
C
F
R
zsh 4.3.4% <file1 while read;do printf "%s=%d\n" "$REPLY" "${#$(<file)//[^$REPLY]}";done
A=9
C=7
F=4
R=2

awk 'BEGIN{ while( getline < "firstfile" ) { len = length($0); for ( i=1; i<=len; i++ ) { arr[substr($0, i, 1)]++ } }} { printf "%s=%d\n",  $0, arr[$0] }' secondfile

#!/usr/bin/env sh

# @(#) s1       Demonstrate split of line into characters, filter, sort, count.

set -o nounset
echo

debug=":"
debug="echo"

## Use local command version for the commands in this demonstration.

echo "(Versions used in this script displayed with local utility "version")"
version bash sed grep sort uniq

echo

FILE=${1-data1}

sed -e 's/\(.\)/\1\n/g' $FILE |
grep -f data2 |
sort |
uniq -c

exit 0

% ./s1

(Versions used in this script displayed with local utility version)
GNU bash, version 2.05b.0(1)-release (i386-pc-linux-gnu)
GNU sed version 4.1.2
grep (GNU grep) 2.5.1
sort (coreutils) 5.2.1
uniq (coreutils) 5.2.1

      9 A
      7 C
      4 F
      2 R

% describe -c data1
    1 lines read
    1 words read
   40 chars read

   39 length of longest line
    1 occurrences
    1 line at which first seen
    1 line at which last seen

   39 length of shortest (non-zero length) line
    1 occurrences
    1 line at which first seen
    1 line at which last seen

  1:1 columns:lines.
       1 newline
       9 A
       1 B
       7 C
       4 F
       1 G
       2 H
       4 J
       2 R
       2 S
       2 T
       5 V

awk 'BEGIN{FS=""}
 FNR==NR{
     for(i=1;i<=NF;i++){
          a[$i]++
     }
     next;
 }
 { print $1,a[$1]}
' "file" "file2"