Revert "Add fix for O_NONBLOCK file-descriptor as output pipe"

This reverts commit be8f7d1716.

This was reverted as with this commit the program would consume large amounts
of cpu time just looping and calling the write function, which would not block.

shadermeh.c

@@ -51,7 +51,7 @@ static int write_retry(int fd, const void *buffer, size_t size)
 		int ret = write(fd, buffer, size);
 
 		if (ret < 0) {
-			if (errno == EINTR || errno == EAGAIN)
+			if (errno == EINTR)
 				continue;
 			perror("write");
 			return -1;
@@ -71,11 +71,12 @@ static const struct option long_opts[] = {
 	{ "width", required_argument, NULL, 'w' },
  	{ "height", required_argument, NULL, 'h' },
 	{ "shader", required_argument, NULL, 's' },
+	{ "sampling-rate", required_argument, NULL, 'r' },
 	{ "to-stdout", no_argument, NULL, 'S' },
 	{ NULL, 0, NULL, 0 },
 };
 
-static const char *short_opts = "w:h:s:S";
+static const char *short_opts = "w:h:s:S:r";
 
 static const char *usage_str =
 "shadermeh OPTIONS...\n"
@@ -90,6 +91,8 @@ static const char *usage_str =
 "  --shader, -s <shader file>\n"
 "\n";
 
+#define SND_BUFFER_SIZE   512
+
 int main(int argc, char **argv)
 {
 	GLuint u_iResolution, u_iTime, u_iTimeDelta, u_iFrame;
@@ -103,6 +106,9 @@ int main(int argc, char **argv)
 	bool to_stdout = false;
 	window *wnd;
 	int i;
+	unsigned int sampling_rate = 0;
+	float in_samples[SND_BUFFER_SIZE];   /* Raw input floats from -1...1 */
+	float norm_samples[SND_BUFFER_SIZE]; /* Normalized samples from 0...1 */
 
 	/******************** parse options ************************/
 	width = 800;
@@ -123,6 +129,9 @@ int main(int argc, char **argv)
 		case 's':
 			shader_file = optarg;
 			break;
+		case 'r':
+			sampling_rate = strtol(optarg, NULL, 10);
+			break;
 		case 'S':
 			to_stdout = true;
 			break;