This option sets the margins within which the compiler interprets the source code in your program file. Data outside these margins is not interpreted as source code, though it is included in your source listing if you request one.
.-2-. .-72-. >>-MARGINS--(--+-m-+--,--+-n--+--+------+--)------------------->< '-,--c-'
ABBREVIATIONS: MAR
Variable-length records are effectively padded with blanks to give them the maximum record length.
Any other character is an error and is replaced by a blank.
Do not use a value of c that is greater than the maximum length of a source record, because this causes the format of the listing to be unpredictable. To avoid this problem, put the carriage control characters to the left of the source margins for variable-length records.
Specifying MARGINS(,,c) is an alternative to using %PAGE and %SKIP statements (described in PL/I Language Reference).
DEFAULT: MARGINS (2 72)