diff --git a/tools/flock/src/flock.c b/tools/flock/src/flock.c index 3ac3a4bebc..37ab0ea72d 100644 --- a/tools/flock/src/flock.c +++ b/tools/flock/src/flock.c @@ -133,6 +133,7 @@ int main(int argc, char *argv[]) int do_close = 0; int err; int status; + int open_flags = 0; char *eon; char **cmd_argv = NULL, *sh_c_argv[4]; const char *filename = NULL; @@ -266,6 +267,21 @@ int main(int argc, char *argv[]) if ( timeout_expired ) exit(1); /* -w option set and failed to lock */ continue; /* otherwise try again */ + case EBADF: /* since Linux 3.4 (commit 55725513) */ + /* Probably NFSv4 where flock() is emulated by fcntl(). + * Let's try to reopen in read-write mode. + */ + if (!(open_flags & O_RDWR) && + type != LOCK_SH && + filename && + access(filename, R_OK | W_OK) == 0) { + + close(fd); + open_flags = O_RDWR; + fd = open(filename, open_flags); + break; + } + /* go through */ default: /* Other errors */ if ( filename ) fprintf(stderr, "%s: %s: %s\n", program, filename, strerror(err));