now you can specifiy the slowdown

code/C/slowprint.c

@@ -1,14 +1,35 @@
 #include <stdio.h>
+#include <stdlib.h>
 #include <time.h>
 #include <unistd.h>
 
 int main(int argc, char *argv[])
 {
-int c;
+int		c, sec, nano;
 struct timespec	ts;
+int		slowdown = 300;		/* set a default value */
+float		delay;
+/*
+ *	get the desired slowdown from command-line
+ */
+if (2 == argc) {
+	if (1 != sscanf(argv[1], "%d", &slowdown)) {
+		fprintf(stderr, "%s: bad arg, sorry\n", argv[0]);
+		exit(1);
+		}
+	if (slowdown < 1) {
+		fprintf(stderr, "%d is invalid\n", slowdown);
+		exit(1);
+		}
+	}
 
-ts.tv_sec = 0;
-ts.tv_nsec = 115 * 1000 * 1000;
+/* convert the slowdown value to delay */
+delay = 1.0 / (float)slowdown;
+sec  = (int)delay;
+nano = (int)(1000*1000*1000*(delay - (int)delay));
+
+ts.tv_sec  = sec;
+ts.tv_nsec = nano;
 while ( EOF != (c=getchar()) )
 	{
 	putchar(c);