| seek | (file) statement |
| Syntax | A seekStatement is one of:
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| Description | Random access of both source (ASCII or EBCDIC) and internal form (binary) files is provided by the seek and tell statements. The seek statement repositions the specified file so that the next input/output operation will begin at the specified point (filePosition) in the file. The fileNumber must specify a file that is open with seek capability. The filePosition is a non-negative integer offset in bytes from the beginning of the file. Usually, this is a number returned by the tell statement. (The first position in the file is position zero.) Form (b) specifies that the next operation is to begin at the position immediately following the current end of the file. A filePosition of zero specifies that the next operation is to start at the beginning of the file. Seeking to a position beyond the current end of the file and then writing, automatically fills the intervening positions with the internal representation of zero.
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| Example | This example shows how to use seek to append to the end of a file.
var employeeRecord :
record
name : string ( 30 )
pay : int
end record
var fileNo : int
open : fileNo, "payroll", write, seek, mod
seek : fileNo, * % Seek to the end of the file
write : fileNo, employeeRecord
% This record is added to the end of the file
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| See also | read, write, open, close, tell, get and put statements. Another example use of seek is given with the explanation of the tell statement.
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