1 files changed, 86 insertions, 0 deletions
diff --git a/pkg/tbtables/tbyscn.x b/pkg/tbtables/tbyscn.x
new file mode 100644
index 00000000..27e277ba
--- /dev/null
+++ b/pkg/tbtables/tbyscn.x
@@ -0,0 +1,86 @@
+include "tbtables.h"
+
+# tbyscn -- Y set columns to null
+# Write INDEF values for specified columns in a range of rows in a table.
+# Note:  This routine assumes that EOS = 0 (or SZB_CHAR=1) because the buffer
+# for setting char values to indef is not packed.
+#
+# Phil Hodge,  1-Apr-1993  Include short datatype.
+# Phil Hodge,  2-Jun-1997  Replace INDEFD with TBL_INDEFD.
+
+procedure tbyscn (tp, fd, colptr, numcols, firstrow, lastrow)
+
+pointer tp			# i: pointer to table descriptor
+pointer colptr[numcols]		# i: array of pointers to descr of new columns
+int	fd			# i: identifies the data file for a table
+int	numcols			# i: the number of new columns
+int	firstrow		# i: the first row to be set to indef
+int	lastrow			# i: the last row to be set to indef
+
+pointer sp
+pointer charbuf			# Scratch for character string column
+long	offset			# Location (chars) for writing in table
+int	j, k			# Loop indexes
+int	datatype		# Data type of a column
+int	dlen			# Number of char in an element of the table
+short	sbuf
+bool	boolbuf			# Buffer for writing Boolean values
+long	tbyoff()
+errchk	seek, write
+
+begin
+	do k = 1, numcols {
+	    datatype = COL_DTYPE(colptr[k])
+	    if (datatype < 0)
+		datatype = TY_CHAR
+	    dlen = COL_LEN(colptr[k])
+	    offset = tbyoff (tp, colptr[k], firstrow)
+	    switch (datatype) {
+	    case TY_REAL:
+		do j = 1, lastrow-firstrow+1 {
+		    call seek (fd, offset)
+		    call write (fd, INDEFR, dlen)
+		    offset = offset + dlen
+		}
+	    case TY_DOUBLE:
+		do j = 1, lastrow-firstrow+1 {
+		    call seek (fd, offset)
+		    call write (fd, TBL_INDEFD, dlen)
+		    offset = offset + dlen
+		}
+	    case TY_INT:
+		do j = 1, lastrow-firstrow+1 {
+		    call seek (fd, offset)
+		    call write (fd, INDEFI, dlen)
+		    offset = offset + dlen
+		}
+	    case TY_SHORT:
+		# We need this because INDEFS in the call to WRITE would be
+		# interpreted as an integer rather than as a short int.
+		sbuf = INDEFS
+		do j = 1, lastrow-firstrow+1 {
+		    call seek (fd, offset)
+		    call write (fd, sbuf, dlen)
+		    offset = offset + dlen
+		}
+	    case TY_BOOL:
+		boolbuf = false
+		do j = 1, lastrow-firstrow+1 {
+		    call seek (fd, offset)
+		    call write (fd, boolbuf, dlen)
+		    offset = offset + dlen
+		}
+	    case TY_CHAR:
+		call smark (sp)
+		call salloc (charbuf, dlen, TY_CHAR)
+		do j = 1, dlen
+		    Memc[charbuf+j-1] = EOS	# N.B. this assumes EOS = 0
+		do j = 1, lastrow-firstrow+1 {
+		    call seek (fd, offset)
+		    call write (fd, Memc[charbuf], dlen)
+		    offset = offset + dlen
+		}
+		call sfree (sp)
+	    }
+	}
+end