8.1.1 Field Descriptor Syntax

A field descriptor takes one of the following forms:

[r]c
[r]cw
[r]cw.m
[r]cw.d [Ee]
r
Is the optional repeat count. If it is omitted, the repeat count is assumed to be 1.
c
Is a format code (I, O, Z, F, E, D, G, L, or A).
w
Is the external field width, in characters. Each data item in the external medium is called an external field.
m
Is the minimum number of characters that must appear within the field (including leading zeros).
d
Is the number of characters to the right of the decimal point.
E
In this context, identifies an exponent field.
e
Is the number of characters in the exponent.

The terms r, w, m, d, and e must all be unsigned integer constants or variable format expressions. The following table shows the processor ranges for these values:

Term  VAX Range  Alpha Range 
r  1 through 32767 (2**15-1)   1 through 2147483647 (2**31-1) 
w  1 through 32767  1 through 2147483647 
m  0 through 255 (2**8-1)  0 through 32767 (2**15-1) 
d  0 through 255  0 through 32767 
e  1 through 255  1 through 32767 

PARAMETER constants cannot be used as values for r, w, m, d, or e.

The field descriptors are as follows:

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