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# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
include "mtio.h"
# MTPOSITION -- Position the device to the indicated file and record.
# We are called to position the device by device name, not to position
# an open magtape file.
procedure mtposition (mtname, file, record)
char mtname[ARB] #I device to be positioned
int file #I desired file number
int record #I desired record number
int junk
pointer sp, mtspec, device, devcap
errchk mtparse, mtopen
int mtopen()
begin
call smark (sp)
call salloc (device, SZ_FNAME, TY_CHAR)
call salloc (mtspec, SZ_FNAME, TY_CHAR)
call salloc (devcap, SZ_DEVCAP, TY_CHAR)
# Get device name (including node! prefix) from mtname.
call mtparse (mtname,
Memc[device], SZ_FNAME, junk, junk, Memc[devcap], SZ_DEVCAP)
# Encode new mtname and open device to position to desired file.
# Note that we do not return until positioning is complete. Thus,
# "mtposition(device,1)" is a rewind with wait.
call mtencode (Memc[mtspec], SZ_FNAME,
Memc[device], file, record, Memc[devcap])
call close (mtopen (Memc[mtspec], READ_ONLY, 1))
call sfree (sp)
end
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