working named pipe and pipe simple with c and golang

Makefile

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+.PHONY: all clean test pipe named-pipe
+.ONESHELL:
+
+all: clean
+	echo "going to run all ipc/ffi examples"
+	sleep 1;
+	make test;
+	make pipe;
+
+test:
+	mkdir -p test;
+	cd test;
+	pwd;
+	cd ..;
+	# note: below line stays in root dir because no `\` at the end of previous line
+	rm -rf test;
+
+pipe:
+	cd pipe;
+	gcc test_pipe.c -o test_pipe_c_program;
+	go build -o test_pipe_go_program main.go;
+	./test_pipe_go_program
+
+named-pipe:
+	cd named_pipe;
+	gcc test_named_pipe_receiver.c -o test_named_pipe_receiver_c_program;
+	go build -o test_named_pipe_sender_go_program main.go;
+	./test_named_pipe_receiver_c_program & ./test_named_pipe_sender_go_program;
+
+clean:
+	echo "cleaning..."
+	rm -rf pipe/test_pipe_c_program pipe/test_pipe_go_program
+	rm -rf named_pipe/test_named_pipe_receiver_c_program named_pipe/test_named_pipe_sender_go_program
+

go.mod

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+module github.com/talksik/ipc_and_ffi_example
+
+go 1.21.4

named_pipe/main.go

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+package main
+
+import (
+	"fmt"
+	"os"
+	"syscall"
+)
+
+// createNamedPipe creates a named pipe (FIFO)
+func createNamedPipe(pipeName string) error {
+	err := syscall.Mkfifo(pipeName, 0666)
+	if err != nil && !os.IsExist(err) {
+		return err
+	}
+	return nil
+}
+
+func main() {
+	// Create a named pipe (FIFO)
+	pipeName := "my_pipe"
+	err := createNamedPipe(pipeName)
+	if err != nil {
+		fmt.Println("Error creating named pipe:", err)
+		return
+	}
+
+	// Open the named pipe for writing
+	pipe, err := os.OpenFile(pipeName, os.O_WRONLY, os.ModeNamedPipe)
+	if err != nil {
+		fmt.Println("Error opening named pipe for writing:", err)
+		return
+	}
+	defer pipe.Close()
+
+	// Write data to the named pipe
+	message := "Hello from the writer program!"
+	_, err = pipe.WriteString(message)
+	if err != nil {
+		fmt.Println("Error writing to named pipe:", err)
+		return
+	}
+}

named_pipe/test_named_pipe_receiver.c

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+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+int main() {
+  const char *pipeName = "my_pipe";
+
+  // Open the named pipe for reading
+  int fd = open(pipeName, O_RDONLY);
+  if (fd == -1) {
+    perror("Error opening named pipe for reading");
+    return 1;
+  }
+
+  // Read data from the named pipe
+  char buffer[100];
+  ssize_t bytesRead = read(fd, buffer, sizeof(buffer));
+  if (bytesRead == -1) {
+    perror("Error reading from named pipe");
+    close(fd);
+    return 1;
+  }
+
+  // Print the received data
+  printf("Data read from the named pipe: %.*s\n", (int)bytesRead, buffer);
+
+  // Close the named pipe
+  close(fd);
+
+  return 0;
+}

pipe/main.go

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+package main
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+)
+
+func main() {
+	message := "Hello from Go!"
+
+	// Create a pipe
+	reader, writer, err := os.Pipe()
+	if err != nil {
+		fmt.Println("Error creating pipe:", err)
+		return
+	}
+
+	// Execute the C program
+	cmd := exec.Command("./test_pipe_c_program")
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	cmd.Stdin = reader
+
+	// Start the C program
+	if err := cmd.Start(); err != nil {
+		fmt.Println("Error starting C program:", err)
+		return
+	}
+
+	// Write the message to the pipe
+	_, err = writer.Write([]byte(message))
+	if err != nil {
+		fmt.Println("Error writing to pipe:", err)
+		return
+	}
+
+	// Close the write end of the pipe
+	writer.Close()
+
+	// Wait for the C program to finish
+	if err := cmd.Wait(); err != nil {
+		fmt.Println("Error waiting for C program:", err)
+		return
+	}
+}

pipe/test_pipe.c

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+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+int main() {
+  printf("starting C program!\n");
+
+  char buffer[100];
+  ssize_t bytesRead = read(STDIN_FILENO, buffer, sizeof(buffer));
+
+  if (bytesRead < 0) {
+    perror("Error reading from pipe");
+    return 1;
+  }
+
+  printf("C Program received: %.*s\n", (int)bytesRead, buffer);
+
+  return 0;
+}