This example sorts an input file by column using bubble sort to swap lines into the correct ascending order by a specified field.

awk_sort_by_col.awk

# This program sorts input by a specified column
# Author: Katherine Chuang (@katychuang on Github)
# example awk -v column=2 -f prog.awk data.csv
# 
# Program Steps:
# 1. Read input and store items in an array of array. 
# 2. Sort by column specified (user input letter c)
# 3. Print the sorted version

BEGIN {
    if(!column) {
        print "-----> no column value defined, setting to default 1"
        column = 1;
    }
    
    print "_Input File, read in line by line_"
}

# Reads in every line and store into array of arrays
{
  for (f = 1; f <= NF; f++){
    a[FNR][f] = $f;
  }

  show_row(a[FNR], ("Line " FNR ))
}

END {
  print "Done reading file, begin sorting"
  sort_by_col(a,column)
  
  printf("\n_Final result, sorted by col %s_\n", col)
  show_matrix(a,column)
}

# sort so that the rows are in ascending order by specified column
# this is an implementation of bubblesort
function sort_by_col(arr, col) {
  for(idx=1; idx<=length(arr); idx++){
   for(left=1; left<=length(arr)-idx; left++){
    right = left + 1;
    if(arr[left][col] > arr[right][col])
      swap_rows(arr[left], arr[right]);
   }
  }
}

# swaps two rows, each is an array
function swap_rows(A,B){
  for(i in A){
    temp[i] = A[i]
  }
  for(i in B){
    A[i] = B[i]
    B[i] = temp[i]
  }
}

# print output
function show_matrix(matrix, col){
  for(i in matrix){
    show_row(matrix[i], "Line " i)
  }
}
  
# show items in an array
function show_row(myarray, rowid){
  printf("%s: ", rowid)
  for(e in myarray)
    printf("%s ",myarray[e]);
  printf("\n")
}

# arrays are passed by reference https://www.gnu.org/software/gawk/manual/html_node/Pass-By-Value_002fReference.html

data.csv

ten 10
nine 9
eight 8
seven 7
six 6
five 5
four 4
three 3
two 2
one 1

makefile

# Example of running this make target with a user specified value is: make COL=2 

COL ?= 1  # sets default value if not provided 

default:
  awk -v column=$(COL) -f sorted_records_by_col.awk data.csv