[hackers] [sbase] tail: Use fstat in case file is removed || Michael Forney

From: <git_AT_suckless.org>
Date: Fri, 14 Jul 2017 07:51:01 +0200 (CEST)

commit 1ab4ac60ff891ee4dcd0ca729e9f897c4f4a1f42
Author: Michael Forney <mforney_AT_mforney.org>
AuthorDate: Mon Jul 3 14:58:51 2017 -0700
Commit: Anselm R Garbe <garbeam_AT_gmail.com>
CommitDate: Fri Jul 14 07:50:52 2017 +0200

    tail: Use fstat in case file is removed

diff --git a/tail.c b/tail.c
index 1ab9d18..ce65a01 100644
--- a/tail.c
+++ b/tail.c
_AT_@ -175,8 +175,8 @@ main(int argc, char *argv[])
                         }
                         if (many)
                                 printf("%s==> %s <==\n", newline ? "\n" : "", *argv);
- if (stat(*argv, &st1) < 0)
- eprintf("stat %s:", *argv);
+ if (fstat(fd, &st1) < 0)
+ eprintf("fstat %s:", *argv);
                         if (!(S_ISFIFO(st1.st_mode) || S_ISREG(st1.st_mode)))
                                 fflag = 0;
                         newline = 1;
_AT_@ -193,16 +193,14 @@ main(int argc, char *argv[])
                         for (;;) {
                                 if (concat(fd, *argv, 1, "<stdout>") < 0)
                                         exit(1);
- /* ignore error in case file was removed, we continue
- * tracking the existing open file descriptor */
- if (!stat(*argv, &st2)) {
- if (st2.st_size < st1.st_size) {
- fprintf(stderr, "%s: file truncated\n", *argv);
- if (lseek(fd, SEEK_SET, 0) < 0)
- eprintf("lseek:");
- }
- st1 = st2;
+ if (fstat(fd, &st2) < 0)
+ eprintf("fstat %s:", *argv);
+ if (st2.st_size < st1.st_size) {
+ fprintf(stderr, "%s: file truncated\n", *argv);
+ if (lseek(fd, SEEK_SET, 0) < 0)
+ eprintf("lseek:");
                                 }
+ st1 = st2;
                                 sleep(1);
                         }
                 }
Received on Fri Jul 14 2017 - 07:51:01 CEST