.help zopdir May84 "System Interface"
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NAME
zopdir -- open a directory file
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SYNOPSIS
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zopdir (osfn, chan)

packed	char osfn[]		# directory file name
int	chan			# channel assigned to file
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DESCRIPTION
The named directory file is opened for sequential access in READ_ONLY mode.
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RETURN VALUE
ERR is returned in \fIchan\fR if the named file does not exist, is not a
directory, or cannot be accessed.  A positive nonzero magic integer is
returned if the operation is successful.
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NOTES
A directory file is opened at the kernel level with \fBzopdir\fR,
is read with \fBzgfdir\fR, and is closed with \fBzcldir\fR.
A directory file is viewed by the high level code as a simple list of
OS filenames; a directory file is interfaced to FIO as a text file and
successive filenames are read by the high level code with \fBgetline\fR.
The text file driver for a directory file is machine independent and
serves only as an interface between FIO and the three directory access
primitives.
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SEE ALSO
zgfdir, zcldir
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