V3/man/man4/pc.4

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.he 'PC (IV)'3/15/72'PC (IV)'
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NAME		pc  --  PC-11 paper tape reader/punch
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DESCRIPTION	ppt___
refers to the PC-11 paper tape reader or punch,
depending on whether it is read or written.

When ppt___ is opened for writing, a 100-character leader
is punched.
Thereafter each byte written is punched on
the tape.  No editing of the characters
is performed.
When the file is closed, a 100-character trailer is punched.

When ppt___ is opened for reading, the process
waits until tape is placed in the reader and the reader
is on-line.
Then requests to read cause the characters read
to be passed back to the program, again without
any editing.
This means that several null leader characters
will usually appear at the beginning of the file.
Likewise several nulls are likely to appear at the end.
End-of-file is generated when the tape runs out.

Seek calls for this file are meaningless.
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FILES		/dev/ppt
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SEE ALSO	--
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BUGS		--