Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.atnf.csiro.au/computing/software/gipsy/sub/gdsi_read.dc2 Дата изменения: Wed Jan 27 01:47:50 1999 Дата индексирования: Fri Jan 16 21:49:23 2009 Кодировка:

Function: GDSI_READ

Purpose: Reads data from (part of) a set.

Category: DATA, IMAGE-IO

File: gdsi_read.c

Author: K.G. Begeman

Use: CALL GDSI_READ( SET, Input CHARACTER*(*)
CLOW, Input INTEGER
CUPP, Input INTEGER
BUFFER, Output REAL ARRAY
BUF_LEN, Input INTEGER
PIXELS_DONE, Output INTEGER
TRANS_ID ) In/Out INTEGER

SET set name
CLOW coordinate word of lower left corner of the
subset to read.
If omitted: read the whole set.
CUPP coordinate word of upper right corner of the
subset to read.
If omitted: CLOW is a subset to read.
BUFFER array where pixels are stored.
BUF_LEN max. number of pixels to read.
If omitted: 1 is assumed.
PIXELS_DONE number of pixels actually read in one call.
Not cumulative for a complete transfer.
If omitted: PIXELS_DONE must be equal to BUF_LEN,
otherwise error code -30 will be
returned in TRANS_ID.
TRANS_ID transfer identification.
= 0 read successful completed.
> 0 unique indentifer if read could not be
completed. This unmodified TRANS_ID must be
used until the read has been completed with
TRANS_ID = 0.
< 0 a GDS error has been detected.
Some special GDSI_READ error codes:
-30 argument PIXELS_DONE omitted, but was
unequal to BUF_LEN.
-31 illegal transfer identifier.
-32 Unable to allocate enough memory.
-36 cannot open data file.
-38 maximum open sets exceeded.

Related Docs: gdsi_write.dc2, gdsi_cancel.dc2.

Updates: May 21, 1987: WZ, istalled.
Dec 21, 1989: WZ, migrated to C.
Jul 5, 1990: KGB, modified document.
Oct 31, 1990: WZ, 'naxis', etc. from setsta -> dsc_file.
Aug 17, 1991: KGB, new algorithm, replaced fopen by open.
Jan 31, 1994: JPT, attempt to open read-only if read-write fails.
Mar 24, 1994: JPT, modified for GDS server.
Jan 15, 1998: VOG, replaced tell() by more common lseek()