https://bugzilla.kernel.org/show_bug.cgi?id=26022 Summary: futimesat and utimensat handle NULL filenames Product: Documentation Version: unspecified Platform: All OS/Version: Linux Tree: Mainline Status: NEW Severity: normal Priority: P1 Component: man-pages AssignedTo: documentation_man-pages@xxxxxxxxxxxxxxxxxxxx ReportedBy: vapier@xxxxxxxxxx Regression: No if you pass futimesat or utimensat a NULL path, the functions will operate on the fd as given. in which case it can be either a fd for a directory or a file. for example, the two calls to futimesat() below will do the same thing: #include <fcntl.h> #include <stdio.h> int main() { int fd = open("f", O_CREAT|O_RDWR, 0777); printf("futimesat = %i\n", futimesat(fd, NULL, NULL)); printf("futimesat = %i\n", futimesat(AT_FDCWD, "f", NULL)); return 0; } same behavior can be observed with utimensat(), but it seems only at the Linux syscall level. the POSIX/C library level will reject a NULL filename with errno==EINVAL, but the Linux kernel will treat the dirfd as an fd. funny enough, while glibc rejects pathname==NULL at its ABI, it relies on the Linux ABI to accept pathname==NULL while implementing other functions. -- Configure bugmail: https://bugzilla.kernel.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are watching the assignee of the bug. -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
