https://bugzilla.kernel.org/show_bug.cgi?id=216168 Bug ID: 216168 Summary: updwtmp(3) doesn't mention need for _GNU_SOURCE for updwtmpx Product: Documentation Version: unspecified Hardware: All OS: Linux Status: NEW Severity: normal Priority: P1 Component: man-pages Assignee: documentation_man-pages@xxxxxxxxxxxxxxxxxxxx Reporter: sam@xxxxxxxxxx Regression: No I think utmpxh's updwtmpx might need _GNU_SOURCE to be defined to be usable? Noticed when investigating a warning when building gdm 42.0: ``` ../gdm-42.0/daemon/gdm-session-record.c:200:9: error: implicit declaration of function ‘updwtmpx’; did you mean ‘updwtmp’? [-Werror=implicit-function-declaration] updwtmpx (GDM_NEW_SESSION_RECORDS_FILE, &session_record); ``` ... but: ``` #if defined(HAVE_UTMPX_H) #include <utmpx.h> #endif #if defined(HAVE_UTMP_H) #include <utmp.h> #endif ``` And config.h, set by Meson, contains HAVE_UTMPX_H, HAVE_UTMP_H, HAVE_UPDWTMP, HAVE_UPDWTMPX. >From looking at glibc-2.35's /usr/include/utmpx.h, I think it might need _GNU_SOURCE? It's guarded by __USE_GNU within glibc headers: ``` [..] #ifdef __USE_GNU /* Change name of the utmpx file to be examined. This function is not part of POSIX and therefore no official cancellation point. But due to similarity with an POSIX interface or due to the implementation it is a cancellation point and therefore not marked with __THROW. */ extern int utmpxname (const char *__file); [...] /* Append entry UTMP to the wtmpx-like file WTMPX_FILE. This function is not part of POSIX and therefore no official cancellation point. But due to similarity with an POSIX interface or due to the implementation it is a cancellation point and therefore not marked with __THROW. */ extern void updwtmpx (const char *__wtmpx_file, const struct utmpx *__utmpx); [...] ``` Aside: a friend points out that NetBSD needs NETBSD_SOURCE defined for it too: https://github.com/NetBSD/src/blob/6c9d506c6146a69f3807ce59b4c063792ef32829/include/utmpx.h#L143. -- You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.
