[PATCH] maint: remove useless (off_t) cast of lseek arg

[Jim Meyering]

These (off_t) casts are anachronistic.
They were useful in pre-ANSI-C days, i.e., before prototypes.
There are two remaining off_t casts, and neither appears useful:
(one is even inconsistently formatted, with no space after the ")" ;-)

  src/shred.c:      if (offset > OFF_T_MAX - (off_t) soff)
  src/truncate.c:          if (ssize > OFF_T_MAX - (off_t)fsize)

So I'll probably remove them, too.

>From d0a9750e08a4cf0329f99a9956ab85f196a81263 Mon Sep 17 00:00:00 2001
From: Jim Meyering <address@hidden>
Date: Sat, 28 May 2011 13:52:13 +0200
Subject: [PATCH] maint: remove useless (off_t) cast of lseek arg

* src/wc.c (wc): Remove unnecessary cast.
* src/head.c (elide_tail_bytes_file, elide_tail_lines_file): Likewise.
* src/tac.c (tac_seekable, tac_file): Likewise.
---
 src/head.c |   10 +++++-----
 src/tac.c  |    4 ++--
 src/wc.c   |    4 ++--
 3 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/src/head.c b/src/head.c
index b3ac7fd..84f9582 100644
--- a/src/head.c
+++ b/src/head.c
@@ -422,8 +422,8 @@ elide_tail_bytes_file (const char *filename, int fd, 
uintmax_t n_elide)
       off_t diff;
       enum Copy_fd_status err;

-      if ((current_pos = lseek (fd, (off_t) 0, SEEK_CUR)) == -1
-          || (end_pos = lseek (fd, (off_t) 0, SEEK_END)) == -1)
+      if ((current_pos = lseek (fd, 0, SEEK_CUR)) == -1
+          || (end_pos = lseek (fd, 0, SEEK_END)) == -1)
         {
           error (0, errno, _("cannot lseek %s"), quote (filename));
           return false;
@@ -438,7 +438,7 @@ elide_tail_bytes_file (const char *filename, int fd, 
uintmax_t n_elide)

       /* Seek back to `current' position, then copy the required
          number of bytes from fd.  */
-      if (lseek (fd, (off_t) 0, current_pos) == -1)
+      if (lseek (fd, 0, current_pos) == -1)
         {
           error (0, errno, _("%s: cannot lseek back to original position"),
                  quote (filename));
@@ -716,8 +716,8 @@ elide_tail_lines_file (const char *filename, int fd, 
uintmax_t n_elide)
          If found, write from current position to OFF, inclusive.
          Otherwise, just return true.  */

-      off_t start_pos = lseek (fd, (off_t) 0, SEEK_CUR);
-      off_t end_pos = lseek (fd, (off_t) 0, SEEK_END);
+      off_t start_pos = lseek (fd, 0, SEEK_CUR);
+      off_t end_pos = lseek (fd, 0, SEEK_END);
       if (0 <= start_pos && start_pos < end_pos)
         {
           /* If the file is empty, we're done.  */
diff --git a/src/tac.c b/src/tac.c
index 2e110fa..65ac6a6 100644
--- a/src/tac.c
+++ b/src/tac.c
@@ -215,7 +215,7 @@ tac_seekable (int input_fd, const char *file)
   size_t match_length1 = match_length - 1; /* Speed optimization, non-regexp. 
*/

   /* Find the size of the input file. */
-  file_pos = lseek (input_fd, (off_t) 0, SEEK_END);
+  file_pos = lseek (input_fd, 0, SEEK_END);
   if (file_pos < 1)
     return true;                       /* It's an empty file. */

@@ -546,7 +546,7 @@ tac_file (const char *filename)
         }
     }

-  file_size = lseek (fd, (off_t) 0, SEEK_END);
+  file_size = lseek (fd, 0, SEEK_END);

   ok = (file_size < 0 || isatty (fd)
         ? tac_nonseekable (fd, filename)
diff --git a/src/wc.c b/src/wc.c
index 702a7a77..d5a0afc 100644
--- a/src/wc.c
+++ b/src/wc.c
@@ -234,8 +234,8 @@ wc (int fd, char const *file_x, struct fstatus *fstatus)
         fstatus->failed = fstat (fd, &fstatus->st);

       if (! fstatus->failed && S_ISREG (fstatus->st.st_mode)
-          && (current_pos = lseek (fd, (off_t) 0, SEEK_CUR)) != -1
-          && (end_pos = lseek (fd, (off_t) 0, SEEK_END)) != -1)
+          && (current_pos = lseek (fd, 0, SEEK_CUR)) != -1
+          && (end_pos = lseek (fd, 0, SEEK_END)) != -1)
         {
           /* Be careful here.  The current position may actually be
              beyond the end of the file.  As in the example above.  */
--
1.7.5.2.660.g9f46c