PC(IV) 10/15/73 PC(IV) NAME pc - PC-11 paper tape reader/punch 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. FILES /dev/ppt BUGS If both the reader and the punch are open simultaneously, the trailer is sometimes not punched. Sometimes the reader goes into a dead state in which it cannot be opened.