PIPE(3) PIPE(3)
NAME
pipe - two-way interprocess communication
SYNOPSIS
bind #| dir
dir/data
dir/ctl
dir/data1
dir/ctl1
DESCRIPTION
An attach(5) of this device allocates two new streams joined
at the device end. X/data and x/ctl are the data and con-
trol channels of one stream and x/data1 and x/ctl1 are the
data and control channels of the other stream.
Data written to one channel becomes available for reading at
the other. Write boundaries are preserved: each read termi-
nates when the read buffer is full or after reading the last
byte of a write, whichever comes first.
Written data is buffered in kernel stream blocks. The
writer will block once the stream is full, typically after
32768 bytes or 16 writes. The writer will resume once the
stream is less than half full.
If there are multiple writers, each write is guaranteed to
be available in a contiguous piece at the other end of the
pipe. If there are multiple readers, each read will return
data from only one write.
The pipe(2) system call performs an attach of this device
and returns file descriptors to the new pipe's data and
data1 files. The files are open with mode ORDWR.
SEE ALSO
pipe(2)
SOURCE
/sys/src/9/port/devpipe.c
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