[hackers] [sbase] [PATCH 09/10] tail: Use fstat in case file is removed

[Michael Forney]

---
 tail.c | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/tail.c b/tail.c
index ad97308..000be62 100644
--- a/tail.c
+++ b/tail.c
@@ -133,7 +133,7 @@ main(int argc, char *argv[])
                        }
                        if (many)
                                printf("%s==> %s <==\n", newline ? "\n" : "", 
*argv);
-                       if (stat(*argv, &st1) < 0)
+                       if (fstat(fileno(fp), &st1) < 0)
                                eprintf("stat %s:", *argv);
                        if (!(S_ISFIFO(st1.st_mode) || S_ISREG(st1.st_mode)))
                                fflag = 0;
@@ -153,15 +153,13 @@ main(int argc, char *argv[])
                                if (ferror(fp))
                                        eprintf("fgetc %s:", *argv);
                                clearerr(fp);
-                               /* 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);
-                                               rewind(fp);
-                                       }
-                                       st1 = st2;
+                               if (fstat(fileno(fp), &st2) < 0)
+                                       eprintf("fstat:");
+                               if (st2.st_size < st1.st_size) {
+                                       fprintf(stderr, "%s: file truncated\n", 
*argv);
+                                       rewind(fp);
                                }
+                               st1 = st2;
                                sleep(1);
                        }
                }
-- 
2.11.0