tr(1): don't use indirect variable, supplement comment

[Luka Krmpotić]

Hello,

I suggest this simplification in the "tr [-Ccs] string1 string2"
section of main. It makes it easier to understand what's
happening in the -C case.

Luka

diff --git a/usr.bin/tr/tr.c b/usr.bin/tr/tr.c
index ab78898a986..a47fb409f34 100644
--- a/usr.bin/tr/tr.c
+++ b/usr.bin/tr/tr.c
@@ -167,8 +167,9 @@ main(int argc, char *argv[])
  /*
  * tr [-Ccs] string1 string2
  * Replace all characters (or complemented characters) in string1 with
- * the character in the same position in string2.  If the -s option is
- * specified, squeeze all the characters in string2.
+ * the character in the same position in string2. If string2 runs out
+ * of characters (or with -Cc option), use the last one specified. If
+ * the -s option is specified, squeeze all the characters in string2.
  */
  if (argc != 2)
  usage();
@@ -183,23 +184,21 @@ main(int argc, char *argv[])
  if (!next(&s2))
  errx(1, "empty string2");

- /* If string2 runs out of characters, use the last one specified. */
- ch = s2.lastch;
  if (sflag)
  while (next(&s1)) {
- translate[s1.lastch] = ch = s2.lastch;
- squeeze[ch] = 1;
+ translate[s1.lastch] = s2.lastch;
+ squeeze[s2.lastch] = 1;
  (void)next(&s2);
  }
  else
  while (next(&s1)) {
- translate[s1.lastch] = ch = s2.lastch;
+ translate[s1.lastch] = s2.lastch;
  (void)next(&s2);
  }

  if (cflag)
  for (cnt = 0, p = translate; cnt < NCHARS; ++p, ++cnt)
- *p = *p == OOBCH ? ch : cnt;
+ *p = *p == OOBCH ? s2.lastch : cnt;

  if (sflag)
  for (lastch = OOBCH; (ch = getchar()) != EOF;) {