Make a directory for each row within the given text file?

Question

I'm trying to write a bash shell script that will read the data from a given (as an argument) file, and for each row in the file, make a sub-directory under the given (as an argument) directory.

The script is named studentDir and the input file is named studentInfo.txt.
Here is two lines from it:

Sara Smith Freshman Marketing
James Lucas Junior Engineering

On the command line the user would write the script name, the txt file name, and the directory where the new directories should be stored. I think it would be like this:

$ studentDir studentInfo.txt .

Which will create the sub-directories in the current directory.

The directories should be named LLLLFF.
For example:

SmitSa
LucaJa

(The other info from the input file is not needed)

I think to get the names I would use:

DIRNAME=$(cut -d' ' -f2 | cut -c1-4 ; cut -d' ' -f1 | cut -c1-2) 
mkdir "$DIRNAME" 

But I'm not sure what command would create a directory for each row, and how I could do it recursively for each one.

Answer 1

awk solution

awk '{print substr($2,1,4) substr($1,1,2)}' file

gives you the directory names.

mkdir $(awk '{print substr($2,1,4) substr($1,1,2)}' file)

creates the directories (if they are not too many). For huge numbers (10,000+) you can use:

awk '{print substr($2,1,4) substr($1,1,2)}' file | xargs --delimiter=\\n mkdir

bash solution

awk is not necessary, the shell can do that itself:

while read first last rest; do mkdir -p "${last:0:4}${first:0:2}"; done <file

Answer 2

You could use perl. Saying:

perl -lanE 'mkdir substr(@F[1],0,4) . substr(@F[0],0,2)' studentInfo.txt

would create the desired directories.

Answer 3

Try this:

arr=($(cut -d ' ' -f1,2 < $*))
mkdir $(for ((i=0;i<${#arr[@]};i=i+2)); do echo ${arr[$i+1]:0:4}${arr[$i]:0:2}; done)

The first line will create an array with only the first 2 fields from the input. Each element in the array will have two fields (first, last). The second line will go through each element in the array and substitute each field according the requirement and make a new directory out of each new formed entry.