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2024-06-15Modernize and fix doc’s “Date and Time” (BZ 31876)Paul Eggert1-44/+0
POSIX.1-2024 (now official) specifies tm_gmtoff and tm_zone. This is a good time to update the manual’s “Date and Time” chapter so I went through it, fixed some outdated stuff that had been in there for decades, and improved it to match POSIX.1-2024 better and to clarify some implementation-defined behavior. Glibc already conforms to POSIX.1-2024 in these matters, so this is merely a documentation change. * manual/examples/strftim.c: Use snprintf instead of now-deprecated function asctime. Check for localtime failure. Simplify by using puts instead of fputs. Prefer ‘buf, sizeof buf’ to less-obvious ‘buffer, SIZE’. * manual/examples/timespec_subtract.c: Modernize to use struct timespec not struct timeval, and rename from timeval_subtract.c. All uses changed. Check for overflow. Do not check for negative return value, which ought to be OK since negative time_t is OK. Use GNU indenting style. * manual/time.texi: Document CLOCKS_PER_SEC, TIME_UTC, timespec_get, timespec_getres, strftime_l. Document the storage lifetime of tm_zone and of tzname. Caution against use of tzname, timezone and daylight, saying that these variables have unspecified values when TZ is geographic. This is what glibc actually does (contrary to what the manual said before this patch), and POSIX is planned to say the same thing <https://austingroupbugs.net/view.php?id=1816>. Also say that directly accessing the variables is not thread-safe. Say that localtime_r and ctime_r don’t necessarily set time zone state. Similarly, in the tzset documentation, say that it is called by ctime, localtime, mktime, strftime, not that it is called by all time conversion functions that depend on the time zone. Say that tm_isdst is useful mostly just for mktime, and that other uses should prefer tm_gmtoff and tm_zone instead. Do not say that strftime ignores tm_gmtoff and tm_zone, because it doesn’t do that. Document what gmtime does to tm_gmtoff and tm_zone. Say that the asctime, asctime_r, ctime, and ctime_r are now deprecated and/or obsolescent, and that behavior is undefined if the year is < 1000 or > 9999. Document strftime before these now-obsolescent functions, so that readers see the useful function first. Coin the terms “geographical format” and “proleptic format” for the two main formats of TZ settings, to simplify exposition. Use this wording consistently. Update top-level proleptic syntax to match POSIX.1-2024, which glibc already implements. Document the angle-bracket quoted forms of time zone abbreviations in proleptic TZ. Say that time zone abbreviations can contain only ASCII alphanumerics, ‘+’, and ‘-’. Document what happens if the proleptic form specifies a DST abbreviation and offset but omits the rules. POSIX says this is implementation-defined so we need to document it. Although this documentation mentions ‘posixrules’ tersely, we need to rethink ‘posixrules’ since I think it stops working after 2038. Clarify wording about TZ settings beginning with ‘;’. Say that timegm is in ISO C (as of C23). Say that POSIX.1-2024 removed gettimeofday. Say that tm_gmtoff and tm_zone are extensions to ISO C, which is clearer than saying they are invisible in a struct ISO C enviroment, and gives us more wiggle room if we want to make them visible in strict ISO C, something that ISO C allows. Drop mention of old standards like POSIX.1c and POSIX.2-1992 in the text when the history is so old that it’s no longer useful in a general-purpose manual. Define Coordinated Universal Time (UTC), time zone, time zone ruleset, and POSIX Epoch, and use these phrases more consistently. Improve TZ examples to show more variety, and to reflect current practice and timestamps. Remove obsolete example about Argentina. Add an example for Ireland. Don’t rely on GCC extensions when explaining ctime_r. Do not say that difftime produces the mathematically correct result, since it might be inexact. For clock_t don’t say “as in the example above” when there is no such example, and don’t say that casting to double works “properly and consistently no matter what”, as it suffers from rounding and overflow. Don’t say broken-down time is not useful for calculations; it’s merely painful. Say that UTC is not defined before 1960. Rename Time Zone Functions to Time Zone State. All uses changed. Update Internet RFC 822 → 5322, 1305 → 5905. Drop specific years of ISO 8601 as they don’t matter. Minor style changes: @code{"..."} → @t{"..."} to avoid overquoting in info files, @code → @env for environment variables, Daylight Saving Time → daylight saving time, white space → whitespace, prime meridian → Prime Meridian.
2024-01-01Update copyright dates with scripts/update-copyrightsPaul Eggert1-1/+1
2023-01-06Update copyright dates with scripts/update-copyrightsJoseph Myers1-1/+1
2022-01-01Update copyright dates with scripts/update-copyrightsPaul Eggert1-1/+1
I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 7061 files FOO. I then removed trailing white space from math/tgmath.h, support/tst-support-open-dev-null-range.c, and sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following obscure pre-commit check failure diagnostics from Savannah. I don't know why I run into these diagnostics whereas others evidently do not. remote: *** 912-#endif remote: *** 913: remote: *** 914- remote: *** error: lines with trailing whitespace found ... remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
2021-01-02Update copyright dates with scripts/update-copyrightsPaul Eggert1-1/+1
I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 6694 files FOO. I then removed trailing white space from benchtests/bench-pthread-locks.c and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this diagnostic from Savannah: remote: *** pre-commit check failed ... remote: *** error: lines with trailing whitespace found remote: error: hook declined to update refs/heads/master
2020-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers1-1/+1
2019-09-07Prefer https to http for gnu.org and fsf.org URLsPaul Eggert1-1/+1
Also, change sources.redhat.com to sourceware.org. This patch was automatically generated by running the following shell script, which uses GNU sed, and which avoids modifying files imported from upstream: sed -ri ' s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g ' \ $(find $(git ls-files) -prune -type f \ ! -name '*.po' \ ! -name 'ChangeLog*' \ ! -path COPYING ! -path COPYING.LIB \ ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \ ! -path manual/texinfo.tex ! -path scripts/config.guess \ ! -path scripts/config.sub ! -path scripts/install-sh \ ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \ ! -path INSTALL ! -path locale/programs/charmap-kw.h \ ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \ ! '(' -name configure \ -execdir test -f configure.ac -o -f configure.in ';' ')' \ ! '(' -name preconfigure \ -execdir test -f preconfigure.ac ';' ')' \ -print) and then by running 'make dist-prepare' to regenerate files built from the altered files, and then executing the following to cleanup: chmod a+x sysdeps/unix/sysv/linux/riscv/configure # Omit irrelevant whitespace and comment-only changes, # perhaps from a slightly-different Autoconf version. git checkout -f \ sysdeps/csky/configure \ sysdeps/hppa/configure \ sysdeps/riscv/configure \ sysdeps/unix/sysv/linux/csky/configure # Omit changes that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines git checkout -f \ sysdeps/powerpc/powerpc64/ppc-mcount.S \ sysdeps/unix/sysv/linux/s390/s390-64/syscall.S # Omit change that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
2019-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers1-1/+1
* All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
2018-12-20manual/examples: Remove redundant "if not"H.J. Lu1-1/+1
Replace "if not, if not," with "if not,". * manual/examples/add.c: Remove redundant "if not". * manual/examples/argp-ex1.c: Likewise. * manual/examples/argp-ex2.c: Likewise. * manual/examples/argp-ex3.c: Likewise. * manual/examples/argp-ex4.c: Likewise. * manual/examples/atexit.c: Likewise. * manual/examples/db.c: Likewise. * manual/examples/dir.c: Likewise. * manual/examples/dir2.c: Likewise. * manual/examples/execinfo.c: Likewise. * manual/examples/filecli.c: Likewise. * manual/examples/filesrv.c: Likewise. * manual/examples/fmtmsgexpl.c: Likewise. * manual/examples/genpass.c: Likewise. * manual/examples/inetcli.c: Likewise. * manual/examples/inetsrv.c: Likewise. * manual/examples/isockad.c: Likewise. * manual/examples/longopt.c: Likewise. * manual/examples/memopen.c: Likewise. * manual/examples/memstrm.c: Likewise. * manual/examples/mkdirent.c: Likewise. * manual/examples/mkfsock.c: Likewise. * manual/examples/mkisock.c: Likewise. * manual/examples/mygetpass.c: Likewise. * manual/examples/pipe.c: Likewise. * manual/examples/popen.c: Likewise. * manual/examples/rprintf.c: Likewise. * manual/examples/search.c: Likewise. * manual/examples/select.c: Likewise. * manual/examples/setjmp.c: Likewise. * manual/examples/sigh1.c: Likewise. * manual/examples/sigusr.c: Likewise. * manual/examples/stpcpy.c: Likewise. * manual/examples/strdupa.c: Likewise. * manual/examples/strftim.c: Likewise. * manual/examples/subopt.c: Likewise. * manual/examples/swapcontext.c: Likewise. * manual/examples/termios.c: Likewise. * manual/examples/testopt.c: Likewise. * manual/examples/testpass.c: Likewise. * manual/examples/timeval_subtract.c: Likewise.
2018-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers1-1/+1
* All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
2017-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers1-1/+1
2016-01-04Update copyright dates with scripts/update-copyrights.Joseph Myers1-1/+1
2015-10-20Convert 29 more function definitions to prototype style (multiple parameters ↵Joseph Myers1-2/+1
in one K&R parameter declaration). This automatically-generated patch converts 29 function definitions in glibc (including one in an example in the manual) from old-style K&R to prototype-style. Following my other recent such patches, this one deals with the case of function definitions where one K&R parameter declaration declares multiple parameters, as in: void foo (a, b) int a, *b; { } Tested for x86_64 and x86 (testsuite, and that installed stripped shared libraries are unchanged by the patch). * crypt/crypt.c (_ufc_doit_r): Convert to prototype-style function definition. (_ufc_doit_r): Likewise. * crypt/crypt_util.c (_ufc_copymem): Likewise. (_ufc_output_conversion_r): Likewise. * inet/inet_mkadr.c (__inet_makeaddr): Likewise. * inet/rcmd.c (rcmd_af): Likewise. (rcmd): Likewise. (ruserok_af): Likewise. (ruserok): Likewise. (ruserok2_sa): Likewise. (ruserok_sa): Likewise. (iruserok_af): Likewise. (iruserok): Likewise. (__ivaliduser): Likewise. (__validuser2_sa): Likewise. * inet/rexec.c (rexec_af): Likewise. (rexec): Likewise. * inet/ruserpass.c (ruserpass): Likewise. * locale/programs/xmalloc.c (xcalloc): Likewise. * manual/examples/timeval_subtract.c (timeval_subtract): Likewise. * math/w_drem.c (__drem): Likewise. * math/w_dremf.c (__dremf): Likewise. * math/w_dreml.c (__dreml): Likewise. * misc/daemon.c (daemon): Likewise. * resolv/res_debug.c (p_fqnname): Likewise. * stdlib/div.c (div): Likewise. * string/memcmp.c (memcmp_bytes): Likewise. * sunrpc/pmap_rmt.c (pmap_rmtcall): Likewise. * sunrpc/svc_udp.c (svcudp_bufcreate): Likewise.
2015-01-02Update copyright dates with scripts/update-copyrights.Joseph Myers1-1/+1
2014-01-01Update copyright notices with scripts/update-copyrightsAllan McRae1-1/+1
2013-01-02Update copyright notices with scripts/update-copyrights.Joseph Myers1-1/+1
2012-03-02BZ #13792: License manual example source files under GPL.Roland McGrath1-0/+17
2012-03-02BZ #13792: Add missing file from last commit.Roland McGrath1-0/+28