COMPUTE LINES

        [SIC\]COMPUTE OutVar LINES FileName [/BLANK]

    Count the number of lines in a formatted file. More precisely, it counts
    the number of carriage returns (same as Linux shell "wc -l"). Be careful
    of missing carriage return at the end of your files.

    The option /BLANK can be used to ignore blank and comment (starting with
    "!") lines, in the same way the command ACCEPT does.