HP 3000 Manuals HP 3000 Manuals
Source File Structure
FORTRAN is column sensitive:
* Compiler directive lines (those starting with keywords preceded by
a dollar sign) begin in column 1.
* All other FORTRAN statements can begin in columns 7 through 72.
This permits indenting to improve program appearance.
* Statement labels appear in columns 1 through 5.
* Column 6 must be blank or contain a digit 0 for all lines except
continuation, comment, and directive lines.
* A C, !, or * in column 1 denotes a comment line.
* A D in column 1 denotes a debug line.
* Tabs in columns 1 to 6 advance to column 7, while tabs in columns
7 to 72 are treated as spaces.
Figure 3-1 shows the required order of FORTRAN statements within
program units.