.help zfiotx May84 "System Interface"
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NAME
zfiotx -- text file driver
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SYNOPSIS
.nf
zopntx (osfn, mode, chan)		# open or create text file
zclstx (chan, status)			# close text file
zgettx (chan, text, maxch,  status)	# get next record
zputtx (chan, text, nchars, status)	# put record
zflstx (chan, status)			# flush output
znottx (chan, loffset)			# note file position
zsektx (chan, loffset, status)		# seek to a line
zstttx (chan, param, lvalue)		# get file status

packed	char osfn[]
char	text[]
int	mode, chan, maxch, nchars, status, param
long	loffset, lvalue
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DESCRIPTION
All text file i/o is via these primitives.  The detailed specifications
of the individual routines are given in separate manual pages.
A text file must be opened or created with \fBzopntx\fR before any i/o
can take place.  Text file i/o is record (line) oriented and is sequential
in nature.  Character data is maintained in ASCII SPP chars above the kernel
and in the host character format below the kernel.
The newline character delimits each line of text.
Seeking is permitted prior to a write but only to the beginning of a line
or to BOF or EOF.  The seek offset of a line may only be determined by a
prior call to \fBznottx\fR when actually reading or writing the file.
Writing is permitted only at EOF.  Output is assumed to be buffered.
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RETURN VALUES
Once a file is opened all references to the file are by the channel number
\fIchan\fR, a magic integer.  A file may not be accessed by name while it
is open.  The i/o primitives return the number of characters read or written
as the status value; 0 is returned when reading at EOF.
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SEE ALSO
zfioty, the manual pages for the individual routines
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