UNIX for Beginners Questions & Answers

[banana]
Text
More text
Etc

[apple]
Stuff
That
Is
Needed

[friend]
Etc
Etc

[apple]
..
..

[banana]
..
..

[friend]
..
..

#!/usr/bin/bash                      
while read line                      
do                                   
if [ "${line:0:1}" = "[" ]           
then                                 
        len=${#line}                 
        (( len = $len - 2 ))         
        outfile=${line:1:$len}       
        echo "$line" >$outfile.txt   
else                                 
        echo "$line" >>$outfile.txt  
fi                                   
done <inputfile                      
 cat *.txt >true_outfile

-bash-3.2# l                                                        
total 48                                                            
-rwxr-xr-x    1 root     sys        232 Oct 12 19:37 i              
-rw-r--r--    1 root     sys         76 Oct 12 19:03 inputfile      
-rw-r--r--    1 root     sys         76 Oct 12 19:37 true_outfile   
-bash-3.2# ./i                                                      
-bash-3.2# l                                                        
total 96                                                            
-rw-r--r--    1 root     sys         30 Oct 12 19:40 apple.txt      
-rw-r--r--    1 root     sys         29 Oct 12 19:40 banana.txt     
-rw-r--r--    1 root     sys         17 Oct 12 19:40 friend.txt     
-rwxr-xr-x    1 root     sys        232 Oct 12 19:37 i              
-rw-r--r--    1 root     sys         76 Oct 12 19:03 inputfile      
-rw-r--r--    1 root     sys         76 Oct 12 19:40 true_outfile   
-bash-3.2#

awk '$NF=$NF OFS' RS= ORS="\n" FS="\n" OFS="\t" file | sort | tr '\t' '\n'
[apple]
Stuff
That
Is
Needed

[banana]
Text
More text
Etc

[friend]
Etc
Etc