NAME

START — position file for reading

SYNOPSIS

boxht = 1/6 + 1/16 boxrad = 1/16 arcrad = 1/16 circlerad = 1/24

E0: circle line right

Start: box "START" line right Filename: box "filename" arrow right to (5.0, Here.y)

line invis down 2/6 from E0.c E0: arrow right 1/16 line

First: box "FIRST" arc cw from E0.start E1: line down 1/6 arc ccw line right linewid - arcrad Last: box "LAST" E2: line down 1/6 + 2 * arcrad from E1.end arc ccw line right linewid - arcrad Key: box "KEY" arc cw line down 1/6 arc ccw Is: box "IS" arc ccw dist = Key.e.y - (Here.y + arcrad) line up dist arc cw line from Key.e to Here CompareOperator: box rad 0 height boxht * 1.5 dashed 1/32 "compare" "operator" line right Name: box "name" arc ccw line to (Here.x, Last.e.y + arcrad) arc cw down line from Last.e to Here move to last arc .start line to (Here.x, First.w.y - arcrad) arc up cw line from First.e to Here arrow right to (5.0, Here.y)

line invis down 7/6 from E0.start E0: arrow right 1/16

arc cw line down 1/8 + 1/6 arc ccw line right linewid - arcrad Key: box "WITH" arc right ccw line up 1/6 - arcrad arc cw Length: box "LENGTH" line right 2 * arcrad Statements: box "expr" arc ccw line to (Here.x, E0.end.y - arcrad) arc up cw line from E0.end to Here arrow right to (5.0, Here.y)

line invis down 5/6 from E0.start E0: arrow right 1/16

arc cw line down 1/6 arc ccw line right linewid - arcrad Invalid: box "INVALID" arc cw line down 1/6 arc ccw Key: box "KEY" arc right ccw line to (Here.x, Invalid.e.y - arcrad) arc cw line from Invalid.e to Here Statements: box width 1.5 * boxwid "error-statements" arc ccw line to (Here.x, E0.end.y - arcrad) arc up cw line from E0.end to Here arrow right to (5.0, Here.y)

line invis down 5/6 from E0.start E0: arrow right 1/16

arc cw line down 1/6 arc ccw line right linewid - arcrad NotInvalid: box height boxht * 1.5 "NOT" "INVALID" arc cw line down 1/6 arc ccw Key: box "KEY" arc right ccw line to (Here.x, NotInvalid.e.y - arcrad) arc cw line from NotInvalid.e to Here Statements: box width 1.5 * boxwid "valid-statements" arc ccw line to (Here.x, E0.end.y - arcrad) arc up cw End: line from E0.end to Here arc cw right line down 1/6 arc ccw down box width 1.5 * boxwid "END-START" arc ccw right line up 1/6 arc cw up line from End.end to (5.5, Here.y) circle

DESCRIPTION

START sets the position within filename where the next sequential READ will read a record by applying compare operator (see below) to a key for the file. filename is an FD entry in DATA DIVISION.

When none of FIRST, LAST, or KEY, is specified, START defaults to KEY EQUAL with the primary key of filename as the key. If KEY is used, name specifies the name of a key field or named key for filename. Alternatively, name may specify a field whose leftmost character is at the beginning of a key for filename.

FIRST and LAST are valid for files whose ORGANIZATION is RELATIVE, or INDEXED. For SEQUENTIAL files, one of FIRST or LAST is required. FIRST positions the file at the first record according the file's key (or, for SEQUENTIAL, at the first physical record); LAST similarly positions the file at the last record. If the file is empty, FIRST and LAST produce an error condition, with FILE-STATUS set according the file's organization.

LENGTH is valid only for a file with INDEXED organization. The whole key is used unless LENGTH is used, in which case expr is an arithmetic expression resulting in an integer value constituting the size of the key.

In its conditional form, START may include either or both of INVALID KEY and NOT INVALID KEY. error-statements and valid-statements are blocks of statements. If no record exists matching the KEY criteria, error-statements are executed. If a matching record is found, valid-statements are executed.

END-START marks the end of the START statement. It can be required when START appears in a conditional statement.