FTS1_DREAD

Obtains a FITS record from a disk file

Description:

This routine reads the byte stream from the FITS disk file and extracts a FITS record of 2880 bytes. The blocksize of the disk file is arbitrary save that it be no more than the maximum FITS blocksize of 28800.

Invocation

CALL FTS1_DREAD ( LU, BLKSIZ, ACTSIZ, LINIT, BUFFER, OFFSET, : RECORD, STATUS )

Arguments

LU = INTEGER (Given)
The logical unit number for the disk-FITS file.
BLKSIZ = INTEGER (Given)
The maximum blocksize and dimension of the file block.
ACTSIZ = INTEGER (Given and Returned)
The actual block size. This need not be a multiple of the FITS record length of 2880 bytes. It must be known on input.
LINIT = LOGICAL (Given)
If true, the current record counter (RECNUM) is reset to one. Should be true if a file is being read for the first time.
BUFFER( ACTSIZ ) = BYTE (Given and Returned)
The buffer containing the block of data. This is only read when %OFFSET does not equal %ACTSIZ, i.e. there are some non-header data within it.
OFFSET = INTEGER (Given and Returned)
The number of bytes in the current block already interpreted.
RECORD( 2880 ) = BYTE (Returned)
The current FITS record. Successive calls will read of the FITS records in sequence.
STATUS = INTEGER(Given and Returned)
Global status value.

Prior requirements