Shell Programming and Scripting

I am inexperienced with scripting and it continues to baffles me speechless

I wrote a script so that it counts the number of subset of files (with different prefix) in all subdirectories under the current directory so that

Code:

find ./ -type d -maxdepth 1 -mindepth 1 > list_of_dir.txt

find all subdirectories under the current directory and output the list to txt file

Code:

sed 's/^...//' <list_of_dir.txt >list_of_dir2.txt

edit the output file so that .//directory becomes directory

Code:

rm list_of_dir.txt

Code:

echo list of data > list_of_data.txt

Code:

for i in {1..$(wc -l < list_of_dir2.txt)}
do
echo "\n$(sed -n "$i"p list_of_dir2.txt)" >> list_of_data.txt
cd ./"$(sed -n "$i"p list_of_dir2.txt)"
ls *.jpeg | awk -F_ '{A[$1 FS $2]++} END {for (j in A) printf "%-20s%4d \n", j, A[j] >> "../list_of_data.txt"}' 
cd ..
done

from each subdirectory in the txt file, output the directory name to file list_of_data, then cd into that directory, then count all the number of subset of files under different prefixes and output the result to list_of_data.txt

The problem is, if I run the script by typing ./scriptname.sh I get the error message

Code:

sed: 1: "{1..23}p": invalid command code .
sed: 1: "{1..23}p": invalid command code .
ls: cannot access *.jpeg: No such file or directory

but if I copy the content of the script and paste it in the terminal window it worked.

sample output

directoryname
directoryname_1 10
directoryname_2 5

directoryname2
directoryname2_1 20
directoryname2_2 30

etc etc

Why is this happening?

How does your script start?

the first line of code is how the script start

Code:

{1..$(wc -l < list_of_dir2.txt)}

This does not work. You cannot put a command there.

Your other commands look like they are using sed and the like to extract a single line per loop. This is extremely poor practice.

Please explain what you are trying to do here.

Thanks for your reply. As I said I am inexperienced I am sure there are much better way to write this.

Can you explain why the code works if I paste it in the terminal but it doesn't if I run it as a script?

As I explained above there are many subdirectories under the current directory. And inside each subdirectory there are a large number of files under different prefixes, like pict_1_1, pict_1_2, pict_2_1, pict_2_2, pict_2_3 etc etc etc

I want to count the number of file under each prefix from every subdirectory. with output like the sample output above into a txt file.

I would also appreciate it if you explain why you meant the extreme poor practice. I am keen to learn.

If a script lacks a #! first line it is sent to sh not bash. See man execvp. Man Page for execvp (opensolaris Section 0) - The UNIX and Linux Forums

I think I am beginning to understand what the problem is. It seems the problem occurs with the sed command in the for loop. the error message

Code:

sed: 1: "{1..23}p": invalid command code .

stems from the fact that there are 23 folder in current directory and maybe I don't truely understand the mechanism of the for loop.....as

Code:

for i in {1..23}

then the

Code:

sed -n "$i"p list_of_dir2.txt

command tries to execute sed {1..23} all at the same time, hence the error.
During the for loop is it not like for i =1 then carries out the commands, then for i=2, carries out the command again etc etc until i=23? Why does sed trying to interpret i=1..23 all at the same time?

Still don't understand why the command runs when typed in terminal window but didn't when ran as script.