initial import

manual/examples/pipe.c

@@ -0,0 +1,66 @@
+#include <sys/types.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+/* Read characters from the pipe and echo them to @code{stdout}.  */
+
+void 
+read_from_pipe (int file)
+{
+  FILE *stream;
+  int c;
+  stream = fdopen (file, "r");
+  while ((c = fgetc (stream)) != EOF)
+    putchar (c);
+  fclose (stream);
+}
+
+/* Write some random text to the pipe. */
+
+void 
+write_to_pipe (int file)
+{
+  FILE *stream;
+  stream = fdopen (file, "w");
+  fprintf (stream, "hello, world!\n");
+  fprintf (stream, "goodbye, world!\n");
+  fclose (stream);
+}
+
+int
+main (void)
+{
+  pid_t pid;
+  int mypipe[2];
+
+/*@group*/
+  /* Create the pipe. */
+  if (pipe (mypipe))
+    {
+      fprintf (stderr, "Pipe failed.\n");
+      return EXIT_FAILURE;
+    }
+/*@end group*/
+
+  /* Create the child process. */
+  pid = fork ();
+  if (pid == (pid_t) 0)
+    {
+      /* This is the child process. */
+      read_from_pipe (mypipe[0]);
+      return EXIT_SUCCESS;
+    }
+  else if (pid < (pid_t) 0)
+    {
+      /* The fork failed. */
+      fprintf (stderr, "Fork failed.\n");
+      return EXIT_FAILURE;
+    }
+  else
+    {
+      /* This is the parent process. */
+      write_to_pipe (mypipe[1]);
+      return EXIT_SUCCESS;
+    }
+}