/*  --- Computer Science, Monash University, Australia 3168,  16/4/1999 ---  */


#include <stdio.h>


main(int   argc,  /* Count of command line arguments (parameters) */
     char *argv[] /* Values of parameters: array of string (pointer to char) */
    )
 { int i;
   FILE *inp;  int ch;


   printf("command line:");
   for(i = 0; i < argc; i++)
      printf(" argv[%d]=\"%s\"", i, argv[i]);   /* print each cmd line param */
   printf("\n");                                /* NB argv[0] = program name */


   inp = stdin;                                 /* default input file, but...*/
                                                /* if there is a genuine     */
   if(argc > 1)                                 /* command line parameter... */
    { inp = fopen(argv[1], "r");                /* mode "r" i.e. read, text  */

      if(!inp)                                  /* error, could not open it  */
       { printf("could not open file \"%s\", halting\n", argv[1]);
         exit(1);
       }
    }

   else                     /* no genuine command line parameters, use stdin */
      printf("no file specified, will echo what you type, end with ^D\n");


   i = 1;                                    /* prove we have the right file */
   printf("%3d: ", 1);
   while((ch = fgetc(inp)) != EOF)             /* read each character in inp */
    { printf("%c", ch);                        /* and print it */
      if(ch == '\n')
         printf("%3d: ", ++i);                 /* number the lines */
    }

 }/*main*/

/* Command-Line Parameters & Opening a Named File, L.Allison Comp Sci Monash */