typr

commit 82b278d63cf3e06ef4cedc97757238945fcc4b50
parent 5211c044e98da94d4eb1acacfe68854d27b25987
Author: Willy Goiffon <contact@z3bra.org>
Date:   Tue, 16 Mar 2021 17:31:30 +0100

Add comments about typing speed calculation

Diffstat:
M
typr.c
 | 
21
++++++++++++++++++++-

1 file changed, 20 insertions(+), 1 deletion(-)
diff --git a/typr.c b/typr.c
@@ -4,6 +4,22 @@
  *
  * Type the text that is under the cursor.
  * The cursor will stop on errors, no need to backspace
+ *
+ *
+ * Typing speed can be calculated using the time(1) and wc(1) commands:
+ *
+ * $ time ./typr file.txt
+ * […]
+ * >> errors: 0
+ *  0m28.64s real     0m00.00s user     0m00.00s system
+ *    ^^^^^ TIMESPENT
+ *
+ * $ wc -w file.txt
+ * 28 file.txt
+ * ^^ WORDCOUNT
+ *
+ * WPM = (WORDCOUNT * 60) / TIMESPENT
+ *       (    28    * 60) / 28.64     = 58 WPM
  */
 
 #include <stdio.h>
@@ -57,6 +73,9 @@ main(int argc, char *argv[])
 
 	f = argc > 1 ? fopen(argv[1], "r") : stdin;
 
+	if (!f)
+		return -1;
+
 	tty = open(_PATH_TTY, O_RDWR);
 
 	tcgetattr(tty, &term);
@@ -77,7 +96,7 @@ main(int argc, char *argv[])
 	fclose(f);
 	close(tty);
 
-	printf(">> errors: %d\n", tot);
+	fprintf(stderr, ">> errors: %d\n", tot);
 	
 	return 0;
 }