in-process-communication/shared-memory/synchronous/pipes-unnamed-simple/README.md
# PIPE UNNAMED SIMPLE EXAMPLE
_A pipe provides a uni-directional communication channel.
This is a very simple example of an unnamed pipe._
**I - IN-PROCESS COMMUNICATION**
* **SHARED MEMORY**
* ASYNCHRONOUS
* SYNCHRONOUS
* [pipes-unnamed-simple](https://github.com/JeffDeCola/my-go-examples/tree/master/in-process-communication/shared-memory/synchronous/pipes-unnamed-simple)
**<- YOU ARE HERE**
* [pipes-unnamed](https://github.com/JeffDeCola/my-go-examples/tree/master/in-process-communication/shared-memory/synchronous/pipes-unnamed)
* [pipes-unnamed-io](https://github.com/JeffDeCola/my-go-examples/tree/master/in-process-communication/shared-memory/synchronous/pipes-unnamed-io)
* **MESSAGE PASSING**
* ASYNCHRONOUS
* [channels-buffered](https://github.com/JeffDeCola/my-go-examples/tree/master/in-process-communication/message-passing/asynchronous/channels-buffered)
* SYNCHRONOUS
* [channels-unbuffered](https://github.com/JeffDeCola/my-go-examples/tree/master/in-process-communication/message-passing/synchronous/channels-unbuffered)
**II - INTER-PROCESS COMMUNICATION (IPC)**
* **SHARED MEMORY**
* ASYNCHRONOUS
* SYNCHRONOUS
* [pipes-named](https://github.com/JeffDeCola/my-go-examples/tree/master/inter-process-communication-ipc/shared-memory/synchronous/pipes-named)
* **MESSAGE PASSING**
* **OPERATING SYSTEM**
* ASYNCHRONOUS
* [message-queues](https://github.com/JeffDeCola/my-go-examples/tree/master/inter-process-communication-ipc/message-passing/operating-system/asynchronous/message-queues)
* [pub-sub-nats-os](https://github.com/JeffDeCola/my-go-examples/tree/master/inter-process-communication-ipc/message-passing/operating-system/asynchronous/pub-sub-nats-os)
* [tcp](https://github.com/JeffDeCola/my-go-examples/tree/master/inter-process-communication-ipc/message-passing/operating-system/asynchronous/tcp)
* SYNCHRONOUS
* [grpc-os](https://github.com/JeffDeCola/my-go-examples/tree/master/inter-process-communication-ipc/message-passing/operating-system/synchronous/grpc-os)
* **NETWORK**
* ASYNCHRONOUS
* [pub-sub-nats-network](https://github.com/JeffDeCola/my-go-examples/tree/master/inter-process-communication-ipc/message-passing/network/asynchronous/pub-sub-nats-network)
* [tcp-ip](https://github.com/JeffDeCola/my-go-examples/tree/master/inter-process-communication-ipc/message-passing/network/asynchronous/tcp-ip)
* SYNCHRONOUS
* [grpc-network](https://github.com/JeffDeCola/my-go-examples/tree/master/inter-process-communication-ipc/message-passing/network/synchronous/grpc-network)
* [rest](https://github.com/JeffDeCola/my-go-examples/tree/master/inter-process-communication-ipc/message-passing/network/synchronous/rest)
Table of Contents
* [PIPES OVERVIEW](https://github.com/JeffDeCola/my-go-examples/tree/master/in-process-communication/shared-memory/synchronous/pipes-unnamed-simple#pipes-overview)
* [CODE](https://github.com/JeffDeCola/my-go-examples/tree/master/in-process-communication/shared-memory/synchronous/pipes-unnamed-simple#code)
* [RUN](https://github.com/JeffDeCola/my-go-examples/tree/master/in-process-communication/shared-memory/synchronous/pipes-unnamed-simple#run)
* [IN-PROCESS AND INTER-PROCESS COMMUNICATION OVERVIEW](https://github.com/JeffDeCola/my-go-examples/tree/master/in-process-communication/shared-memory/synchronous/pipes-unnamed-simple#in-process-and-inter-process-communication-overview)
Documentation and Reference
* Refer to the
[io.Pipe](https://pkg.go.dev/io#Pipe)
package for more info
* Refer to
[my cheat sheets](https://github.com/JeffDeCola/my-cheat-sheets/tree/master/software/development/software-architectures/communication/in-process-and-inter-process-communications-ipc-overview-cheat-sheet)
for a communications overview
## PIPES OVERVIEW
A pipe provides a uni-directional in-process communication channel, where two
ends are involved: reader and writer. Data written to the write end of
the pipe can be read from the read end. A named pipe (FIFO) can be accessed from
different processes whereas an unnamed pipe can be accessed from the same process.
* **MACHINE**: SAME
* **PROCESSES**: IN-PROCESS
* **TYPE**: SHARED MEMORY
* **TIMING**: SYNCHRONOUS
* **DIRECTION**: UNI-DIRECTIONAL
Pipes in go can be used to connect code expecting an io.Reader with
code expecting an io.Writer.
## CODE
Create the pipe using the "io" package,
```go
pr, pw := io.Pipe()
```
Send data (write) to the pipe.
```go
_, err := pw.Write([]byte(data))
```
This writes the data to memory that is shared.
Now when ready, receive data (read) from the pipe (i.e. read from memory),
```go
rcvData := make([]byte, 100)
_, err := pr.Read(rcvData)
```
## RUN
Run,
```bash
go run main.go
```
## IN-PROCESS AND INTER-PROCESS COMMUNICATION OVERVIEW
Refer to
[my cheat sheets](https://github.com/JeffDeCola/my-cheat-sheets/tree/master/software/development/software-architectures/communication/in-process-and-inter-process-communications-ipc-overview-cheat-sheet)
for a more thorough communications overview.
