Shell Programming and Scripting

#!/bin/awk -f
BEGIN {
        FS=":";
}
{
        if ( $2 == "" ) {
                print $1 ": no password!";
        }
}

# ./minusf.awk aa aa aa aa
awk: can't open aa

  
       Gawk's built-in variables are:

       ARGC        The  number  of command line arguments (does not include options to gawk


       ARGIND      The index in ARGV

       ARGV        Array of command line arguments.  The array is indexed from 0 to ARGC
                   cally changing the contents of ARGV can control the files used for data.

akshay@Aix:/tmp$ cat test.awk 
BEGIN{
	for(i=1; i<ARGC; i++)
	  printf("ARG[%d] = %s\n",i,ARGV[i])
}

akshay@Aix:/tmp$ awk -f test.awk user password etc etc
ARG[1] = user
ARG[2] = password
ARG[3] = etc
ARG[4] = etc

./minusf <<< "aa:aa:aa:aa"

# ./minusf.awk 'aa aa aa aa'
awk: can't open aa aa aa aa