SORT-MERGE/XL General User's Guide (32650-90883)

82 Chapter6
SORT-MERGE/XL Commands
INPUT (SORT/XL)
PARAMETERS
MPE XL SORT has two sets of scratch files. If the sort takes place in compatibility mode,
there is one scratch file for which the size is computed as in MPE V/E SORT. If the sort
takes place in native mode, there are two (mapped) scratch files. Both computations are
described below.
Compatibility Mode Scratch File Size
If you want to extimate the scratch file record size (SFRS) and the scratch file size (SFS),
use the following equations:
SFRS+((
rec size + 7)/2) + 4
where
rec size is the input record size in bytes. (You must add the length of the keys to
$STDIN [ X ] Specifies that the input records are to be read from $STDIN[ X ].
In interactive mode a question mark (?) prompt is displayed.
* Entering an asterisk (*) in an interactive session specifies that the
input records are read from the text file TEXT. In this case, the
input records are to follow the >END command, and the list of
records is to be terminated with :EOD.
Recall that TEXT is the formal file designator of the file containing
the SORT/XL commands and that it defaults to $STDIN. Therefore,
if no file equation has been entered against the file TEXT, the input
records are entered from the terminal in interactive mode and are
included in the stream file in batch mode. (The prompt "?" is
displayed for each record in interactive mode.) If a file equation has
been issued, then the records should be part of the file equated to
TEXT (again following the >END command).
fname Specifies the actual file designator. $NULL is not a valid input file.
#records The #records parameter should be specified only if one or more of
the input files is not on disc. It is a positive integer specifying the
upper limit of the number of records sorted. If multiple input files
are specified, it is the total number of records from all input files.
When all input files are on disc, the current end-of-file (EOF)
values are used and #records is ignored. If all input files are not
on disc and #records is not specified, a default value of 10,000 is
assumed by SORT/XL. This parameter cannot be used to extract a
subset of the input file.
rec size A positive integer specifying the maximum allowable number of
bytes in a record. This parameter may be used to set the record size
of the output file, but is used mainly for files containing
variable-length records. When sorting such files, this parameter
should be set to the size of the largest record present in the input.
If rec size is not specified when sorting variable-length record
files, SORT/XL will use the block size as the maximum record size.
This could result in more space than necessary being used for the
scratch file, as well as causing some degradation of performance.