add directory study

study/linux-travel/MINIX-1.5/1.5/Source/commands/echo.c

@@ -0,0 +1,43 @@
+/* echo - echo arguments	Author: Andy Tanenbaum */
+
+#define SIZE 1024
+char buf[SIZE];
+int count;
+main(argc, argv)
+int argc;
+char *argv[];
+{
+  register int i, nflag;
+
+  nflag = 0;
+  if (argc > 1 && argv[1][0] == '-' && argv[1][1] == 'n') {
+	nflag++;
+	argc--;
+	argv++;
+  }
+  for (i = 1; i < argc; i++) {
+	collect(argv[i]);
+	if (i < argc - 1) collect(" ");
+  }
+
+  if (nflag == 0) collect("\n");
+
+  /* Print accumulated output. */
+  if (count > 0) write(1, buf, count);
+  exit(0);
+}
+
+collect(s)
+char *s;
+{
+/* Collect characters.  For efficiency, write them in large chunks. */
+  char c;
+
+  while ((c = *s++) != 0) {
+	if (count == SIZE) {
+		write(1, buf, count);
+		count = 0;
+	}
+	buf[count++] = c;
+  }
+}