Loading using fix format

When loading according to fix format, the input line is divided only according to the format prescription. The data in input lines, therefore, has to be in fixed positions determined in the format prescription.

The position of each item is defined by the sum of the widths of the precedent items on the line and the number of all the separating alphanumeric characters.

In the format prescription

<P:6><N:04>, X=<X>, Y=<Y>

, the prefix must start in column 1, the number in column 7, the coordinate X in column 15, and the coordinate Y in column 30.

The program doesn't test whether the separating characters are identical to the characters defined in the format prescription (after the point number, the program skips four characters and doesn't test whether they are really the characters ", X=").