AWK Assignment and execute operation with variables

Question

I would like to find out how to assign and execute an operation with the value variable.

Suppose that I get these files as a result of ls -A *.pdf | grep -v '^d':

firstOne.pdf
ordenSiq.pdf

Now I'm trying to execute any operation later of assignment, an example:

% ls -lAh ordenSiq.pdf
-rw-r--r--@ 1 joseluisbz  staff    47K Jun 29 15:35 ordenSiq.pdf

Here my attempt (but is not working!)

awk -v thelast="$(ls -A *.pdf | grep -v '^d' | tail -n 1 | awk '{print}')" 'BEGIN {ls -lAh thelast;}'

EDIT

1. Obtaining The Last File With Extension!

% thelast=$(ls -A *.pdf | grep -v '^d' | tail -n 1 | awk '{print}'); awk -v result=$thelast 'BEGIN{print result}' Otutput: ordenSiq.pdf

2. Extracting Only The Name (split)

% thelast=$(ls -A *.pdf | grep -v '^d' | tail -n 1 | awk '{print}'); thename=$(echo ${thelast} | awk '{split($0,a,"."); print a[1]}'); awk -v result="$thename" 'BEGIN{print result}' Output:ordenSiq

3. ALL Extensions For name (concatenation)

% thelast=$(ls -A *.pdf | grep -v '^d' | tail -n 1 | awk '{print}'); thename=$(echo ${thelast} | awk '{split($0,a,"."); print a[1]}'); allexts=$(echo ${thename}'.*'); awk -v result="$allnames" 'BEGIN{print result}' Output:ordenSiq.*

or

thelast=$(ls -A *.pdf | grep -v '^d' | tail -n 1 | awk '{print}'); thename=$(echo ${thelast} | awk '{split($0,a,"."); print a[1]}'); awk -v allexts=${thename}".*" 'BEGIN{print allexts}'

4. Execution of command with variable

I would like to obtain something like:

% ls -lAh ordenSiq.*
-rw-r--r--  1 joseluisbz  staff     0B Jul 15 12:34 ordenSiq.abc
-rw-r--r--  1 joseluisbz  staff     0B Jul 15 12:34 ordenSiq.def
-rw-r--r--@ 1 joseluisbz  staff    47K Jun 29 15:35 ordenSiq.pdf
% 

ERROR:

% thelast=$(ls -A *.pdf | grep -v '^d' | tail -n 1 | awk '{print}'); thename=$(echo ${thelast} | awk '{split($0,a,"."); print a[1]}'); awk -v allexts=${thename}".*" 'BEGIN{system(ls -lAh allexts)}' Output:

sh: 0ordenSiq.*: command not found

And with

thelast=$(ls -A *.pdf | grep -v '^d' | tail -n 1 | awk '{print}'); thename=$(echo ${thelast} | awk '{split($0,a,"."); print a[1]}'); awk -v allexts=${thename}".*" 'BEGIN{system(ls -lAh $allexts)}' Output:

awk: illegal field $(ordenSiq.*), name "allexts"
 source line number 1

Some Working example:

% root1="/webroot"; echo | awk -v r=$root1 '{ print "shell variable $root1 value is " r}' Output:

shell variable $root1 value is /webroot

Statically Works!

% ls -lAh ordenSiq.*                                                                                                                                                                    
-rw-r--r--  1 joseluisbz  staff     0B Jul 15 12:34 ordenSiq.abc
-rw-r--r--  1 joseluisbz  staff     0B Jul 15 12:34 ordenSiq.def
-rw-r--r--@ 1 joseluisbz  staff    47K Jun 29 15:35 ordenSiq.pdf
%

And the variable's value is correct!

% thelast=$(ls -A *.pdf | grep -v '^d' | tail -n 1 | awk '{print}'); thename=$(echo ${thelast} | awk '{split($0,a,"."); print a[1]}'); allexts=$(echo ${thename}'.*'); echo ${allexts} Output:

ordenSiq.*

But doing this, do not work;

% thelast=$(ls -A *.pdf | grep -v '^d' | tail -n 1 | awk '{print}'); thename=$(echo ${thelast} | awk '{split($0,a,"."); print a[1]}'); allexts=$(echo ${thename}'.*'); ls -lAh $allexts Output:

ls: ordenSiq.*: No such file or directory

QUESTION:

What is wrong in my steps in order to perform the final operation with variables (with and without AWK)?

Answer 1

{ls -lAh thelast;}

This is not correct way of using shell command in GNU AWK, you should prepare string with command and then use system function, so for example if you want to sleep for 5 seconds at beginning you might do

awk 'BEGIN{system("sleep 5")}'

Keep in mind that system function returns exit status code (see linked documentation for further discussion), not output of command.

Answer 2

I think this is what you're trying to do:

thelast=$(find . -type f -name '*.pdf' -printf '%T@\t%p\n' | sort -n | cut -f2- | tail -n 1)
thename="${thelast%.pdf}"
allexts=( "$thename".* )
ls -lh "${allexts[@]}"

As for what's wrong with your original code:

% thelast=$(ls -A *.pdf | grep -v '^d' | tail -n 1 | awk '{print}'); thename=$(echo ${thelast} | awk '{split($0,a,"."); print a[1]}'); allexts=$(echo ${thename}'.*'); ls -lAh $allexts

1. It's trying to parse the output of ls, see https://mywiki.wooledge.org/ParsingLs
2. It's removing the names of files that start with d for unknown reasons.
3. It's not listing the files in time order
4. It's using awk '{print}' which does nothing but copy the input to the output.
5. It's got unquoted variables (copy/paste your code into http://shellcheck.net and it'll tell you about the basic issues)
6. echo ${thename}'.*' is leaving the part that needs to be double-quoted unquoted and then single-quoting the part that needs to be unquoted.
7. Using split() in awk as you are would corrupt file names that contain multiple .s.
8. There may be other issues that aren't as obvious, idk.