ttyn.3

UNIX v6源代码 这几乎是最经典的unix版本 unix操作系统设计和莱昂氏unix源代码分析都是用的该版

.th TTYN III 1/15/73
.sh NAME
ttyn \*- return name of current typewriter
.sh SYNOPSIS
.ft B
jsr	pc,ttyn
.s3
ttyn(file)
.s3
.ft R
.sh DESCRIPTION
.it Ttyn
hunts up the last character of the name of the
typewriter which is the standard input (from \fIas\fR)
or is specified by the
argument
.it file
descriptor (from C).
If \fIn\fR is returned, the
typewriter name is then ``/dev/tty\fIn\fR''.
.s3
.bd x
is returned if the indicated file does not correspond to a
typewriter.
.sh BUGS