7.1.1 Control List

The control list is composed of parameters that specify one or more of the following:

• The logical unit to act upon

• The internal file to act upon

• The format (explicit or list-directed) to use for data editing; if explicit, the format specification

• The NAMELIST group-name specification

• The number of a record to access in direct-access mode

• The name of a variable that contains the completion status of an I/O operation

• The label of the statement that receives control if an error or end-of-file condition occurs

• The key field and key of reference to access a keyed-access record (VMS only)

The statement type can always be determined by the contents of its control list. For example, the control list of a formatted I/O statement always contains a format specifier (FMT=f or f), while that of a list-directed I/O statement always contains an asterisk (*) in place of a format specifier.

The control list takes the following form:

(p [,p] . . . )

p

Is a specifier taking the following form:

[keyword =] value

[keyword =] value

Is one of several possible keywords and values that are described in the following sections.