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9.91 utmpx.h ¶

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/utmpx.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

• This header file is missing on some platforms: FreeBSD 8.4, OpenBSD 7.2, Minix 3.1.8, mingw, MSVC 14, Android 13.0.
• While some platforms have the struct utmpx field ut_user, older platforms have the field ut_name.
• The struct utmpx field ut_exit does not exist on some platforms: macOS, FreeBSD, AIX, Cygwin.
• The struct utmpx field ut_session does not exist on some platforms: macOS, FreeBSD, AIX, HP-UX, Cygwin.
• The struct utmpx field ut_addr or ut_addr_v6 or ut_ss does not exist on some platforms: macOS, FreeBSD, AIX, Solaris.
• On some platforms, the struct utmpx field ut_tv is not of type struct timeval. Instead, it is a different struct with tv_sec and tv_usec members that may have different types than the members of struct timeval: glibc 2.42 on platforms where time_t was historically 32 bits and where log file formats were not changed when 64-bit time_t was introduced.
• On some platforms, this API does not support timestamps past the year 2038: glibc 2.39 on 32-bit platforms like x86 and ARM where time_t was historically 32 bits; later glibc versions support timestamps up to the year 2106, by changing ut_tv.tv_sec’s type to be a 32-bit unsigned integer.
• On some platforms, this header misbehaves if the year2038 or year2038-recommended modules are used and the program is configured without the --disable-year2038 option. The readutmp module works around this problem: glibc 2.38 on 32-bit platforms like x86 and ARM where time_t was historically 32 bits. See Avoiding the year 2038 problem.