Vertical from Command Line

[Trumpman06]

Im trying to get the operands from argv to print vertically. for some reason, after it gets to the end of an operand, it starts to print the next operand.

int col= 0, maxlength = 0, row= 0;
	for(col = optind; col < argc; col++){
		if(maxlength < strlen(argv[col])){
			maxlength = strlen(argv[col]);
        }
    }
       char c;
	for(row = 0; row < maxlength; row++){
		for(col = optind; col < argc; col++){
			if (row < strlen(argv[col])){
			   	   c = argv[col][row];
			     argv[col][row]=c;
		        putchar(argv[col][row]);}
			else{
				argv[col][row]=' ';
				putchar(' ');}
        }
			putchar('\n');
	}
    }

[Kennedy]

			if (row < strlen(argv[col])){
			   	   c = argv[col][row];
			     argv[col][row]=c;
		        putchar(argv[col][row]);}
			else{
				argv[col][row]=' ';
				putchar(' ');}
        }

Why are you assigning argv[bla] to c then back again?

Next, if you assign ' ' to argv[bla] and bla oversteps the array, that's bad.

[MK27]

Im trying to get the operands from argv to print vertically. for some reason, after it gets to the end of an operand, it starts to print the next operand.

Because you do this:

argv[col][row]=' ';

That overwrites the last character in argv[col], which would have been '\0'. Since **argv is contained sequentially in memory, you have now connected argv[col] to argv[col+1] with a space.

If you add some printf's, I am sure you will notice the strlen on the next pass has increased to include the next string in the array (and possibly more, if they have already had their null terminator overwritten).

Even if this had not happened, it is a very bad idea to continue writing spaces to an array when you know it's allocated space has been exceeded.