glibc/FAQ
Ulrich Drepper dfd2257ad9 Update.
1997-10-12 05:09  Ulrich Drepper  <drepper@cygnus.com>

	* libio/Makefile (routines): Remove iofprintf.
	* stdio-common/fprintf.c [USE_IN_LIBIO]: Define _IO_fprintf.
	* libio/filedoalloc.c: Use _G_stat64 instead of stat.
	* libio/fileops.c (_IO_file_open): Change to take extra argument
	indicating whether 32 or 64 bit mode is wanted.
	* libio/iofopen.c: Call _IO_file_open with extra argument set to 0.
	* libio/iofopen64.c: Call _IO_file_open with extra argument set to 0.
	* libio/iolibio.h (_IO_freopen, _IO_freopen64): Likewise.
	* libio/iofgetpos.c: Pretty print.
	* libio/iofgetpos64.c: Use _IO_fpos64_t for local variable `pos'.

	* manual/conf.texi: Document all the _SC_ and _CS_ constants.
	* manual/creature.texi: Document _LARGEFILE_SOURCE, _LARGEFILE64_SOURCE
	and _FILE_OFFSET_BITS.
	* manual/llio.texi: Document truncate and ftruncate.
	* manual/stdio.texi: Document positional parameters for printf.

	* math/Makefile (headers): Add tgmath.h.
	(libm-support): Remove s_lrint, s_llrint, s_lround, and s_llround and
	move to ...
	(libm-calls): ... here.  Add scalbln, s_nextafterx and s_fma.
	* math/libm-test.c (lround_test, llround_test): Test for all FP formats
	by using FUNC().
	* math/libm.map: Add fma, fmaf, fmal, nextafterx, nextafterxf,
	nextafterxl, scalbln, scalblnf, scalblnl, lrintf, lrintl, llrintf,
	llrintl, lroundf, lroundl, llroundf, and llroundl.
	* math/math.h: Document new platform specific macros from mathdef.h.
	Remove declaration of lrint, llrint, lround, and llround.
	* math/test-double.c: Define TEST_DOUBLE.
	* math/test-idouble.c: Likewise.
	* math/test-float.c: Define TEST_FLOAT.
	* math/test-ifloat.c: Likewise.
	* math/tgmath.h: New file.
	* math/bits/mathcalls.h: Add nextafterx, scalbln, fma, lrint, llrint,
	lround, and llround.
	Change second argument of scalbn to `int'.
	* sysdeps/libm-ieee754/s_fma.S: New file.
	* sysdeps/libm-ieee754/s_fmaf.S: New file.
	* sysdeps/libm-ieee754/s_fmal.S: New file.
	* sysdeps/libm-i387/s_fma.S: New file.
	* sysdeps/libm-i387/s_fmaf.S: New file.
	* sysdeps/libm-i387/s_fmal.S: New file.
	* sysdeps/libm-i387/s_llrint.S: Change to take double argument.
	* sysdeps/libm-i387/s_lrint.S: Likewise.
	* sysdeps/libm-i387/s_llrintf.S: New file.
	* sysdeps/libm-i387/s_llrintl.S: New file.
	* sysdeps/libm-i387/s_lrintf.S: New file.
	* sysdeps/libm-i387/s_lrintl.S: New file.
	* sysdeps/libm-ieee754/s_llrint.c: Remove version which works on
	80bit double.
	* sysdeps/libm-ieee754/s_lrint.c: Likewise.
	* sysdeps/libm-ieee754/s_llrintf.S: New file.
	* sysdeps/libm-ieee754/s_llrintl.S: New file.
	* sysdeps/libm-ieee754/s_lrintf.S: New file.
	* sysdeps/libm-ieee754/s_lrintl.S: New file.
	* sysdeps/libm-i387/s_scalbln.c: New file.  Empty file.
	* sysdeps/libm-i387/s_scalblnf.c: New file.  Empty file.
	* sysdeps/libm-i387/s_scalblnl.c: New file.  Empty file.
	* sysdeps/libm-i387/s_scalbn.c: Add scalbln as alias.
	* sysdeps/libm-i387/s_scalbnf.c: Add scalblnf as alias.
	* sysdeps/libm-i387/s_scalbnl.c: Add scalblnl as alias.
	* sysdeps/libm-ieee754/s_llround.c: Remove version which works on
	80bit double.
	* sysdeps/libm-ieee754/s_lround.c: Likewise.
	* sysdeps/libm-ieee754/s_llroundf.c: Likewise.
	* sysdeps/libm-ieee754/s_llroundl.c: Likewise.
	* sysdeps/libm-ieee754/s_lroundf.c: Likewise.
	* sysdeps/libm-ieee754/s_lroundl.c: Likewise.
	* sysdeps/libm-ieee754/s_nextafterl.c: Add alias fo nextafterxl.
	* sysdeps/libm-ieee754/s_nextafterx.c: New file.
	* sysdeps/libm-ieee754/s_nextafterxf.c: New file.
	* sysdeps/libm-ieee754/s_nextafterxl.c: New file.
	* sysdeps/libm-ieee754/s_scalbln.c: New file.
	* sysdeps/libm-ieee754/s_scalblnf.c: New file.
	* sysdeps/libm-ieee754/s_scalblnl.c: New file.
	* sysdeps/libm-ieee754/s_scalbn.c: Change to take `int' as second arg.
	* sysdeps/libm-ieee754/s_scalbnf.c: Likewise.
	* sysdeps/libm-ieee754/s_scalbnl.c: Likewise.

	* stdlib/stdlib.h: Protect declarations of __strto*l_internal functions
	by #ifdefs since they are duplicated in inttypes.h.
	* sysdeps/wordsize-32/inttypes.h: Add definition of strtoimax and
	strtoumax plus needed declarations.

	* sysdeps/generic/confname.h (_SC_AIO_LISTIO_MAX): Fix typo.

1997-10-09  Andreas Jaeger  <aj@arthur.rhein-neckar.de>

	* locale/programs/locfile.c (locfile_read): Correct while loop.

	* db2/makedb.c (main): Add missing parameter for error output.
	(process_input): Likewise.

	* resolv/gethnamaddr.c (getanswer): Rewrite a bit to avoid warning.

1997-10-12 05:05  Ulrich Drepper  <drepper@cygnus.com>

	* libc-map: Add __bzero, __mempcpy.

1997-10-10 18:51  David S. Miller  <davem@tanya.rutgers.edu>

	* sysdeps/unix/sysv/linux/sparc/bits/ioctls.h: Remove dependencies
	on kernel_termios.h

1997-10-09  10:24  Thorsten Kukuk  <kukuk@vt.uni-paderborn.de>

	Add the changes from the Solaris 2.6 header files, use the new public
	defines/functions.
	* nis/nis_addmember.c: Updated.
	* nis/nis_checkpoint.c: Updated.
	* nis/nis_creategroup.c: updated.
	* nis/nis_destroygroup.c: Updated.
	* nis/nis_getservlist.c: Updated.
	* nis/nis_ismember.c: Updated.
	* nis/nis_lookup.c: Updated.
	* nis/nis_modify.c: Updated.
	* nis/nis_ping.c: Updated.
	* nis/nis_print.c: Updated.
	* nis/nis_print_group_entry.c: Updated.
	* nis/nis_remove.c: Updated.
	* nis/nis_removemember.c: Updated.
	* nis/nis_xdr.c: Updated.
	* nis/nss_nisplus/nisplus-alias.c: Updated.
	* nis/nss_nisplus/nisplus-ethers.c: Updated.
	* nis/nss_nisplus/nisplus-hosts.c: Updated.
	* nis/nss_nisplus/nisplus-network.c: Updated.
	* nis/nss_nisplus/nisplus-parser.c: Updated.
	* nis/nss_nisplus/nisplus-proto.c: Updated.
	* nis/nss_nisplus/nisplus-rpc.c: Updated.
	* nis/nss_nisplus/nisplus-service.c: Updated.
	* nis/rpcsvc/nis.h: Updated.
	* nis/rpcsvc/nis.x: Updated.
	* nis/rpcsvc/nis_object.x: Updated.
	* nis/rpcsvc/nis_tags.h: Updated.
	* nis/rpcsvc/nislib.h: Updated.

	* nis/lckcache.c: Removed, since Sun has dropped the directory
	signatures.  The old cache version is now a security risk and not
	longer supported by Sun.
	* nis/nis_cache.c: Likewise.
	* nis/rpcsvc/nis_cache.h: Likewise.
	* nis/rpcsvc/nis_cache.x: Likewise.

	* nis/nis_call.c: Remove calls to the cache functions.

	* nis/libnsl.map: Remove cache and depending functions.
	* nis/nis_intern.h: Likewise.

	* nis/nis_add.c: Remove #include <rpcsvc/nislib.h>.
	* nis/nis_domain_of.c: Likewise.
	* nis/nis_domain_of_r.c: Likewise.
	* nis/nis_error.c: Likewise.
	* nis/nis_file.c: Likewise.
	* nis/nis_local_names.c: Likewise.
	* nis/nis_mkdir.c: Likewise.
	* nis/nis_rmdir.c: Likewise.
	* nis/nis_subr.c: Likewise.
	* nis/nis_verifygroup.c: Likewise.

	* nis/nis_clone.c: Removed, replaced by ...
	* nis/nis_clone_dir.c: New.
	* nis/nis_clone_obj.c: New.
	* nis/nis_clone_res.c: New.
	* nis/nis_table.c: Fixed bugs shown through the new clone functions.

	* nis/nis_defaults.c: Fixed a lot of race conditions.

	* nis/nis_free.c: Rewritten.

	* sunrpc/auth_des.c: Fix use of free'ed pointer.

	* nis/Makefile (libnsl-routines): Remove nis_clone, nis_cache and
	lckcache.  Add nis_clone_dir, nis_clone_obj, and nis_clone_res.

1997-10-09  Andreas Jaeger  <aj@arthur.rhein-neckar.de>

	* wctype/test_wctype.c (TEST): Add parens to avoid ambiguity.

1997-10-08  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* include/features.h: Don't crash if _XOPEN_SOURCE is defined to
	be empty.

1997-10-09 05:54  Ulrich Drepper  <drepper@cygnus.com>

	* nss/digits_dots.c: Place `result' in resbuf and not in `buffer'.
	* nss/getXXbyYY_r.c: Make sure digits_dots.c sees `resbuf' as
	struct and not a pointer.  Little optimizations.

1997-10-09 05:00  Ulrich Drepper  <drepper@cygnus.com>

	* sysdeps/stub/getenv.c: Remove unused file.
	* sysdeps/stub/lxstat.c: Likewise.
	* sysdeps/stub/morecore.c: Likewise.
	* sysdeps/stub/putenv.c: Likewise.
	* sysdeps/stub/sbrk.c: Likewise.
	* sysdeps/stub/setenv.c: Likewise.
	* sysdeps/stub/sysd-stdio.c: Likewise.
	* sysdeps/stub/sysdep.h: Likewise.
	Reported by Zack Weinberg <zack@rabi.phys.columbia.edu>.

1997-10-09 04:58  Ulrich Drepper  <drepper@cygnus.com>

	* configure.in: Add __bzero definition to DWARF2 unwind test.
	Reported by David S. Miller <davem@caip.rutgers.edu>.

1997-10-07  Paul Eggert  <eggert@twinsun.com>

	* intl/loadmsgcat.c (_nl_load_domain):
	Fix &&/|| typo when checking file size.
	Check for overflow when stuffing off_t into size_t.

1997-10-07 18:11  Ulrich Drepper  <drepper@cygnus.com>

	* time/africa: Update from tzdata1997i.

1997-10-07  Andreas Jaeger  <aj@arthur.rhein-neckar.de>

	* posix/globtest.sh: Add arguments for name of dynamic linker and
	call dynamic linker to execute globtest.

	* posix/Makefile (tests): Supply arguments to globtest.sh.

1997-10-07  Andreas Jaeger  <aj@arthur.rhein-neckar.de>

	* nis/rpcsvc/ypupd.h: Add missing __END_DECLS.

1997-10-03  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* libc.map: Add mempcpy, prctl.

1997-09-30  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* sysdeps/generic/memcmp.c: Avoid warnings.
	* sysdeps/generic/memset.c: Likewise.
	* sysdeps/generic/strchr.c: Likewise.
	* sysdeps/generic/strlen.c: Likewise.

1997-09-29  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* malloc/Makefile ($(objpfx)mtrace): Fix typo.

1997-09-29  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* sysdeps/m68k/dl-machine.h (elf_machine_rela): Fix last change.
	The R_68K_GLOB_DAT and R_68K_JMP_SLOT relocations really ignore
	the addend, Richard.
	(elf_machine_fixup_plt): Don't add the addend.
	(elf_machine_plt_value): New function.

	* sysdeps/alpha/dl-machine.h (elf_machine_plt_value): New
	function.
	* sysdeps/sparc/sparc32/dl-machine.h (elf_machine_plt_value): New
	function.
	* sysdeps/sparc/sparc64/dl-machine.h (elf_machine_plt_value): New
	function.
	* sysdeps/powerpc/dl-machine.h (elf_machine_plt_value): New
	function.
	* sysdeps/i386/dl-machine.h (elf_machine_plt_value): New
	function.

	* elf/dl-runtime.c (fixup, profile_fixup): Don't add in the
	addend, instead let the machine dependent setup decide.

1997-09-20  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* sysdeps/m68k/m68020/bits/string.h: New file.

1997-10-07 04:27  Richard Henderson  <rth@cygnus.com>

	* Makeconfig (+includes): Add -I$(objpfx).

	* stdlib/longlong.h [__sparc__]: Prototype __udiv_qrnnd.

	* sysdeps/alpha/setjmp.S: __setjmp is the same as _setjmp.  Make
	the former a strong symbol and the later a weak alias.
	* sysdeps/sparc/sparc32/setjmp.S: Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc64/setjmp.S: Likewise.

1997-10-06 21:01  David S. Miller  <davem@tanya.rutgers.edu>

	* sysdeps/unix/sysv/linux/sparc/sparc64/bits/types.h: Make ino_t
	64-bits.
	* sysdeps/unix/sysv/linux/sparc/sparc64/kernel_stat.h: Make st_ino
	member 64-bits as well, to match the kernel.

1997-10-06 19:35  Ulrich Drepper  <drepper@cygnus.com>

	* sysdeps/sparc/sparc64/sub_n.S: Fix typo.
	Patch by Jakub Jelinek <jj@sunsite.ms.mff.cuni.cz>.

1997-10-06 01:09  Zack Weinberg  <zack@rabi.phys.columbia.edu>

	* time/README: Correct list of files from tzcode package.  Add
	contact information for tzcode/tzdata maintainers.  Correct
	spelling of author's name.  Compact lists.

1997-10-06 01:48  Ulrich Drepper  <drepper@cygnus.com>

	* malloc/malloc.h: Remove hook definition without caller argument.
	* malloc/malloc.c: Likewise.

	* string/tester.c: Correct strsep test.

	* string/bits/string2.h: Define __string2_1bptr_p and use it.
	Patch by David S. Miller <davem@tanya.rutgers.edu>.

	* math/Makefile (routines): Add s_clog10.
	* math/libm-test.c: Add test for clog10.
	* math/libm.map: Add clog10{,f,l}.
	* math/bits/cmathcalls.h [__USE_GNU]: Add clog10.
	* sysdeps/libm-ieee754/s_clog10.c: New file.
	* sysdeps/libm-ieee754/s_clog10f.c: New file.
	* sysdeps/libm-ieee754/s_clog10l.c: New file.
	* manual/math.texi: Describe clog10.

	* config.h.in: Add USE_REGPARMS and define internal_function based on
	this.
	* configure.in: Define USE_REGPARMS for ix86 machines.
	* gmon/gmon.c: Mark write_hist, write_call_graph and write_bb_counts
	as internal functions.
	* inet/getnameinfo.c: Likewise for  nrl_domainname.
	* inet/getnetgrent_r.c: Likewise for __internal_setnetgrent_reuse.
	* inet/rcmd.c: Likewise for __icheckhost.
	* intl/dcgettext.c: Likewise for category_to_name and
	guess_category_value.
	* intl/localealias.c: Likewise for read_alias_file.
	* io/fts.c: Likewise for fts_alloc, fts_build, fts_lfree,
	fts_maxarglen, fts_padjust, fts_palloc, fts_sort, and fts_stat.
	* libio/genops.c: Likewise for save_for_backup.
	* malloc/malloc.c (chunk_free, chunk_alloc, chunk_realloc, chunk_align,
	main_trim, heap_trim): Likewise.
	* malloc/mtrace.c (tr_where): Likewise.
	* misc/fstab.c (mnt2fs): Likewise.
	* misc/getttyent.c (skip, value): Likewise.
	* misc/syslog.c (openlog_internal): Likewise.
	* misc/tsearch.c (trecurse, tdestroy_internal): Likewise.
	* nss/nsswitch.c (nss_lookup_function, nss_parse_file, nss_getline,
	nss_parse_service_list, nss_new_service): Likewise.
	* posix/wordexp.c (parse_dollars, parse_backtick, eval_expr): Likewise.
	* resolv/inet_ntop.c (inet_ntop4, inet_ntop6): Likewise.
	* resolv/inet_pton.c (inet_pton4, inet_pton6): Likewise.
	* resolv/res_init.c (res_setoptions): Likewise.
	* stdio-common/printf_fp.c (group_number): Likewise.
	* stdio-common/vfprintf.c (buffered_vfprintf, group_number): Likewise.
	* stdlib/fmtmsg.c (internal_addseverity): Likewise.
	* sunrpc/auth_des.c (synchronize): Likewise.
	* sunrpc/auth_unix.c (marshal_new_auth): Likewise.
	* sunrpc/clnt_perr.c (auth_errmsg): Likewise.
	* sunrpc/key_call.c (key_call): Likewise.
	* sunprc/pmap_rmt.c (getbroadcastnets): Likewise.
	* sunrpc/svc_tcp.c (makefd_xprt): Likewise.
	* sunrpc/svcauth_des.c (cache_init, cache_spot, cache_ref, invalidate):
	Likewise.
	* sunrpc/xdr_rec.c (fix_buf_size, skip_input_bytes, flush_out,
	set_input_fragment, get_input_bytes): Likewise.
	* sysdeps/unix/sysv/linux/getsysstats.c (get_proc_path,
	phys_pages_info): Likewise.
	* sysdeps/unix/sysv/linux/if_index.c (opensock): Likewise.
	* sysdeps/unix/sysv/linux/poll.c (__emulate_poll): Likewise.
	* sysdeps/unix/sysv/linux/readv.c (__atomic_readv_replacement):
	Likewise.
	* sysdeps/unix/sysv/linux/readv.c (__atomic_writev_replacement):
	Likewise.
	* time/strptime.c (strptime_internal): Likewise.
	* time/tzfile.c (find_transition, compute_tzname_max): Likewise.
	* time/tzset.c (compute_change, tz_compute, tzset_internal): Likewise.

	* libc.map: Remove _libio_using_thunks, add _fp_hw and _dl_addr.

	* ctype/ctype.h: Pretty print.
	* grp/grp.h: Likewise.
	* include/libc-symbols.h: Likewise.
	* include/limits.h: Likewise.
	* include/values.h: Likewise.
	* io/fcntl.h: Likewise.
	* io/sys/stat.h: Likewise.
	* libio/stdio.h: Likewise.
	* malloc/malloc.h: Likewise.
	* misc/err.h: Likewise.
	* misc/regexp.h: Likewise.
	* misc/sys/cdefs.h: Likewise.
	* misc/sys/file.h: Likewise.
	* posix/sys/utsname.h: Likewise.
	* posix/sys/wait.h: Likewise.
	* pwd/pwd.h: Likewise.
	* resolv/netdb.h: Likewise.
	* signal/signal.h: Likewise.
	* stdlib/stdlib.h: Likewise.
	* string/endian.h: Likewise.
	* string/memory.h: Likewise.
	* sysdeps/mach/hurd/bits/fcntl.h: Likewise.
	* sysdeps/mach/hurd/sys/param.h: Likewise.
	* sysdeps/unix/sysv/linux/sys/param.h: Likewise.
	* termios/termios.h: Likewise.
	* wcsmbs/wchar.h: Likewise.
	* wctype/wctype.h: Likewise.

	* sysdeps/unix/bsd/bsd4.4/wait3.c: Use __WAIT_STATUS in definition.

	Implement Large File Support API.
	* include/features.h: Add suuport for _LARGEFILE_SOURCE,
	_LARGEFILE64_SOURCE, and _FILE_OFFSET_BITS.
	* libc.map: Add new functions for LFS.
	* dirent/Makefile (routines): Add readdir64 and readdir64_r.
	* dirent/dirent.h: Update readdir prototype for LFS and add new
	prototypes for above functions.
	* io/Makefile (routines): Add xstat64, fxstat64, lxstat64,
	statfs64, fstatfs64, lstat64, open64, lseek64, creat64, and ftw64.
	* io/creat64.c: New file.
	* io/fstat64.c: New file.
	* io/lstat64.c: New file.
	* io/stat64.c: New file.
	* io/ftw64.c: New file.
	* io/ftw.c: Rewrite to allow easy definition of ftw64.
	* io/ftw.h: Add LFS interface.
	* io/fcntl.h: Likewise.
	* io/sys/stat.h: Likewise.
	* io/sys/statfs.h: Likewise.
	* libio/Makefile (routines): Add iofgetpos64, iofopen64, iofsetpos64,
	freopen64, fseeko64, and ftello64.
	* libcio/fseeko64.c: New file.
	* libio/ftello64.c: New file.
	* libio/iofgetpos64.c: New file.
	* libio/iofopen64.c: New file.
	* libio/iofsetpos64.c: New file.
	* libio/fileops.c (_IO_file_fopen): Change to use _IO_off64_t.
	(_IO_file_attach): Likewise.
	(_IO_do_write): Likewise.
	(_IO_file_sync): Likewise.
	(_IO_file_seek): Likewise.
	(_IO_file_seekoff): Likewise.  Use _G_stat64.
	(_IO_file_fopen64): New function.
	(_IO_file_jumps): Initialize showmanyc and imbue.
	* libio/genops.c (_IO_default_seekpos): Change to use _IO_fpos64_t.
	(_IO_default_seekoff): Likewise.
	(_IO_default_seek): Likewise.
	(_IO_default_showmanyc, _IO_default_imbue): New functions.
	* libio/iofopncook.c (_IO_cookie_seek): Change to use _IO_off64_t.
	* libio/iolibio.h: Add prototypes for LFS functions.
	* libio/ioseekoff.c: Change to use _IO_fpos64_t.
	* libio/ioseekpos.c: Likewise.
	* libio/libio.h: Define _IO_fpos64_t and _IO_off64_t.
	(_IO_FILE): Move _offset field to end and change type to _IO_off64_t.
	(_IO_seekoff, _IO_seekpos): Change prototype.
	* libio/libioP.h (_IO_seekoff_t, _IO_seekpos_t, _IO_seek_t): Change
	to use _IO_off64_t.
	Change prototypes for function from the *ops.c files.
	* libio/stdio.h: Add LFS interface definition.
	* libio/strops.c (_IO_str_seekoff): Change to use _IO_fpos64_t.
	* posix/Makefile (routines): Add pread64 and pwrite64.
	* posix/confstr.c: Handle _CS_LFS* requests.
	* posix/getconf.c: Handle LFS* requests.
	* sysdeps/generic/confname.h: Add _CS_LFS* constants.
	* posix/unistd.h: Document _LFS64_LARGEFILE and _LFS64_STDIO.
	Define off_t and off64_t appropriately.  Change prototypes of
	LFS functions.
	* posix/sys/types.h: Add LFS types.
	* resources/Makefile (routines): Add getrlimit64 and setlimit64.
	* resource/sys/resource.h: Change prototypes of LFS functions.
	* stdio-common/Makefile (routines): Add tmpfile64.
	* stdio-common/tmpfile64.c: New file.
	* sysdeps/generic/_G_config.h: Define _G_fpos64_t and _G_off64_t.
	Define _G_OPEN64, _G_LSEEK64, _G_FSTAT64.
	* sysdeps/unix/sysv/linux/_G_config.h: Likewise.
	* sysdeps/generic/bits/resource.h: Add LFS definitions.
	* sysdeps/unix/bsd/sun/sunos4/bits/resource.h: Likewise.
	* sysdeps/unix/sysv/linux/bits/resource.h: Likewise.
	* sysdeps/generic/statfs.h: Use __fsblkcnt_t for some of the fields.
	* sysdeps/unix/sysv/linux/bits/statfs.h: Likewise.
	* sysdeps/unix/sysv/linux/mips/bits/statfs.h: Likewise.
	* sysdeps/generic/types.h: Define LFS types.
	* sysdeps/unix/sysv/linux/alpha/bits/types.h: Likewise.
	* sysdeps/unix/sysv/linux/bits/types.h: Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc64/bits/types.h: Likewise.
	* sysdeps/generic/sys/mman.h: Add LFS definitions.
	* sysdeps/unix/sysv/linux/sys/mman.h: Likewise.
	* sysdeps/generic/mach/hurd/bits/fcntl.h: Add flock LFS extensions.
	* sysdeps/unix/bsd/bits/fcntl.h: Likewise.
	* sysdeps/unix/sysv/linux/alpha/bits/fcntl.h: Likewise.
	* sysdeps/unix/sysv/linux/bits/fcntl.h: Likewise.
	* sysdeps/unix/sysv/linux/mips/bits/fcntl.h: Likewise.
	* sysdeps/generic/mach/hurd/bits/stat.h: Add stat LFS extensions.
	* sysdeps/unix/bsd/bits/stat.h: Likewise.
	* sysdeps/unix/bsd/osf/alpha/bits/stat.h: Likewise.
	* sysdeps/unix/sysv/linux/alpha/bits/stat.h: Likewise.
	* sysdeps/unix/sysv/linux/bits/stat.h: Likewise.
	* sysdeps/unix/sysv/linux/mips/bits/stat.h: Likewise.
	* sysdeps/unix/sysv/linux/sparc/bits/stat.h: Likewise.
	* sysdeps/unix/sysv/sysv4/i386/bits/stat.h: Likewise.
	* sysdeps/unix/sysv/sysv4/solaris2/bits/stat.h: Likewise.
	* sysdeps/posix/open64.c: New file.
	* sysdeps/stub/fstatfs64.c: New file.
	* sysdeps/stub/fxstat64.c: New file.
	* sysdeps/stub/getrlimit64.c: New file.
	* sysdeps/stub/lseek64.c: New file.
	* sysdeps/stub/lxstat64.c: New file.
	* sysdeps/stub/open64.c: New file.
	* sysdeps/stub/pread64.c: New file.
	* sysdeps/stub/pwrite64.c: New file.
	* sysdeps/stub/readdir64.c: New file.
	* sysdeps/stub/readdir64_r.c: New file.
	* sysdeps/stub/setrlimit64.c: New file.
	* sysdeps/stub/statfs64.c: New file.
	* sysdeps/stub/xstat64.c: New file.
	* sysdeps/unix/sysv/linux/llseek.c: Define as __llseek and make
	llseek and lseek64 weak aliases.
	* sysdeps/unix/sysv/linux/lseek64.c: New file.  Empty.
	* sysdeps/unix/sysv/linux/alpha/bits/dirent.h: New file.
	* sysdeps/unix/sysv/linux/bits/dirent.h: Add LFS definitions.

	* sysdeps/posix/tempname.c: Add extra argument to trigger use of
	open64.
	* sysdeps/stub/tempname.c: Likewise.
	* stdio-common/tempnam.c: Call __stdio_gen_tempname with extra
	argument.
	* stdio-common/tmpfile.c: Likewise.
	* stdio-common/tmpnam.c: Likewise.
	* stdio-common/tmpnam_r.c: Likewise.

	* libio/libioP.h: Add definition ofr showmanyc and imbue callbacks.
	* libio/fileops.c (_IO_file_jumps): Initialize showmanyc and imbue.
	* libio/iofopncook.c (_IO_cookie_jumps): Likewise.
	* libio/iopopen.c (_IO_proc_jumps): Likewise.
	* libio/memstream.c (_IO_mem_jumps): Likewise.
	* libio/obprintf.c (_IO_obstack_jumps): Likewise.
	* libio/vsnprintf.c (_IO_strn_jumps): Likewise.
	* libio/strops.c (_IO_str_jumps): Likewise.

	* manual/arith.texi: Add a few words why cabs should be used.
	* manual/llio.texi: Describe sync, fsync, fdatasync.
	Tell about cleanup handlers & fcntl,lseek,write,read,close,open.
	* manual/process.texi: Tell about cleanup handlers & system,waitpid,
	wait.
	* manual/signal.texi: Likewise for pause.
	* manual/terminal.texi: Likewise for tcdrain.
	* manual/time.texi: Document nanosleep.

	* posix/exevp.c: Don't use nested function.

	* stdlib/ucontext.h: New file.
	* sysdeps/i386/sys/ucontext.h: New file.  SysV/i386 API definitions.

	* sunrpc/xcrypt.c (hexval): Make a macro for efficiency.

	* sysdeps/i386/setjmp.h: Make `here` label local.

	* sysdeps/i386/elf/start.S: Define _fp_hw "variable".

	* sysdeps/stub/fstatfs.c: Correct warning.
	* sysdeps/stub/fxstat.c: Likewise.
	* sysdeps/stub/lxstat.c: Likewise.

	* sysdeps/unix/sysv/i386/i686/time.S: New file.

1997-10-03 20:56  Jason Merrill  <jason@yorick.cygnus.com>

	* malloc/obstack.h (obstack_empty_p): New macro.

1997-10-04 17:41  Philip Blundell  <Philip.Blundell@pobox.com>

	* inet/getnameinfo.c (getnameinfo): Remove spurious `#if INET6'.

1997-09-30  Zack Weinberg <zack@rabi.phys.columbia.edu>

	* maint.texi: Add copyright terms for libdb (Sleepycat, Harvard).
	Document new --with-binutils switch; delete reference to
	--with-gnu-as, --with-gnu-ld, --with-gnu-binutils.
	Add to description of --without-fp: a kernel FPU emulator
	is adequate (from FAQ)
	* INSTALL: Regenerated.

1997-09-30 17:29  Richard Henderson  <rth@cygnus.com>

	* sysdeps/sparc/sparc32/dl-machine.h (elf_machine_rela): Move
	_dl_hwcap declaration to ...
	(elf_machine_fixup_plt): ... here.
1997-10-12 04:05:44 +00:00

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Frequently Asked Question on GNU C Library
As every FAQ this one also tries to answer questions the user might have
when using the package. Please make sure you read this before sending
questions or bug reports to the maintainers.
The GNU C Library is very complex. The building process exploits the
features available in tools generally available. But many things can
only be done using GNU tools. Also the code is sometimes hard to
understand because it has to be portable but on the other hand must be
fast. But you need not understand the details to use GNU C Library.
This will only be necessary if you intend to contribute or change it.
If you have any questions you think should be answered in this document,
please let me know.
--drepper@cygnus.com
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q1] ``What systems does the GNU C Library run on?''
[Q2] ``What compiler do I need to build GNU libc?''
[Q3] ``When starting make I get only error messages.
What's wrong?''
[Q4] ``After I changed configure.in I get `Autoconf version X.Y.
or higher is required for this script'. What can I do?''
[Q5] ``Do I need a special linker or archiver?''
[Q6] ``Do I need some more things to compile GNU C Library?''
[Q7] ``When I run `nm -u libc.so' on the produced library I still
find unresolved symbols? Can this be ok?''
[Q8] ``Can I replace the libc on my Linux system with GNU libc?''
[Q9] ``I expect GNU libc to be 100% source code compatible with
the old Linux based GNU libc. Why isn't it like this?''
[Q10] ``Why does getlogin() always return NULL on my Linux box?''
[Q11] ``Where are the DST_* constants found in <sys/time.h> on many
systems?''
[Q12] ``The `gencat' utility cannot process the input which are
successfully used on my Linux libc based system. Why?''
[Q13] ``How do I configure GNU libc so that the essential libraries
like libc.so go into /lib and the other into /usr/lib?''
[Q14] ``When linking with the new libc I get unresolved symbols
`crypt' and `setkey'. Why aren't these functions in the
libc anymore?''
[Q15] ``What are these `add-ons'?''
[Q16] ``When I use GNU libc on my Linux system by linking against
to libc.so which comes with glibc all I get is a core dump.''
[Q17] ``Looking through the shared libc file I haven't found the
functions `stat', `lstat', `fstat', and `mknod' and while
linking on my Linux system I get error messages. How is
this supposed to work?''
[Q18] ``The prototypes for `connect', `accept', `getsockopt',
`setsockopt', `getsockname', `getpeername', `send',
`sendto', and `recvfrom' are different in GNU libc than
on any other system I saw. This is a bug, isn't it?''
[Q19] ``My XXX kernel emulates a floating-point coprocessor for me.
Should I enable --with-fp?''
[Q20] ``How can I compile gcc 2.7.2.1 from the gcc source code using
glibc 2.x?
[Q21] ``On Linux I've got problems with the declarations in Linux
kernel headers.''
[Q22] ``When I try to compile code which uses IPv6 header and
definitions on my Linux 2.x.y system I am in trouble.
Nothing seems to work.''
[Q23] ``When compiling GNU libc I get lots of errors saying functions
in glibc are duplicated in libgcc.''
[Q24] ``I have set up /etc/nis.conf, and the Linux libc 5 with NYS
works great. But the glibc NIS+ doesn't seem to work.''
[Q25] ``After installing glibc name resolving doesn't work properly.''
[Q26] ``I have /usr/include/net and /usr/include/scsi as symlinks
into my Linux source tree. Is that wrong?''
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q1] ``What systems does the GNU C Library run on?''
[A1] {UD} This is difficult to answer. The file `README' lists the
architectures GNU libc is known to run *at some time*. This does not
mean that it still can be compiled and run on them in the moment.
The systems glibc is known to work on in the moment and most probably
in the future are:
*-*-gnu GNU Hurd
i[3456]86-*-linux-gnu Linux-2.0 on Intel
m68k-*-linux-gnu Linux-2.0 on Motorola 680x0
alpha-*-linux-gnu Linux-2.0 on DEC Alpha
powerpc-*-linux-gnu Linux and MkLinux on PowerPC systems
Other Linux platforms are also on the way to be supported but I need
some success reports first.
If you have a system not listed above (or in the `README' file) and
you are really interested in porting it, contact
<bug-glibc@prep.ai.mit.edu>
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q2] ``What compiler do I need to build GNU libc?''
[A2] {UD} It is (almost) impossible to compile GNU C Library using a
different compiler than GNU CC. A lot of extensions of GNU CC are
used to increase the portability and speed.
But this does not mean you have to use GNU CC for using the GNU C
Library. In fact you should be able to use the native C compiler
because the success only depends on the binutils: the linker and
archiver.
The GNU CC is found like all other GNU packages on
ftp://prep.ai.mit.edu/pub/gnu
or better one of the many mirror sites.
You always should try to use the latest official release. Older
versions might not have all the features GNU libc could use.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q3] ``When starting `make' I get only errors messages.
What's wrong?''
[A3] {UD} You definitely need GNU make to translate GNU libc. No
other make program has the needed functionality.
Versions before 3.74 have bugs which prevent correct execution so you
should upgrade to the latest version before starting the compilation.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q4] ``After I changed configure.in I get `Autoconf version X.Y.
or higher is required for this script'. What can I do?''
[A4] {UD} You have to get the specified autoconf version (or a later)
from your favourite mirror of prep.ai.mit.edu.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q5] ``Do I need a special linker or archiver?''
[A5] {UD} If your native versions are not too buggy you can probably
work with them. But GNU libc works best with GNU binutils.
On systems where the native linker does not support weak symbols you
will not get a really ISO C compliant C library. Generally speaking
you should use the GNU binutils if they provide at least the same
functionality as your system's tools.
Always get the newest release of GNU binutils available.
Older releases are known to have bugs that affect building the GNU C
Library.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q6] ``Do I need some more things to compile GNU C Library?''
[A6] {UD} Yes, there are some more :-).
* GNU gettext; the GNU libc is internationalized and partly localized.
For bringing the messages for the different languages in the needed
form the tools from the GNU gettext package are necessary. See
ftp://prep.ai.mit.edu/pub/gnu or better any mirror site.
* lots of diskspace (for i?86-linux this means, e.g., ~170MB; for ppc-linux
even ~200MB).
You should avoid compiling on a NFS mounted device. This is very
slow.
* plenty of time (approx 1h for i?86-linux on i586@133 or 2.5h on
i486@66 or 4.5h on i486@33), both for shared and static only).
Multiply this by 1.5 or 2.0 if you build profiling and/or the highly
optimized version as well. For Hurd systems times are much higher.
For Atari Falcon (Motorola 68030 @ 16 Mhz, 14 Mb memory) James Troup
<J.J.Troup@comp.brad.ac.uk> reports for a full build (shared, static,
and profiled) a compile time of 45h34m.
If you have some more measurements let me know.
* When compiling for Linux:
+ the header files of the Linux kernel must be available in the
search path of the CPP as <linux/*.h> and <asm/*.h>.
* Some files depend on special tools. E.g., files ending in .gperf
need a `gperf' program. The GNU version (part of libg++) is known
to work while some vendor versions do not.
You should not need these tools unless you change the source files.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q7] ``When I run `nm -u libc.so' on the produced library I still
find unresolved symbols? Can this be ok?''
[A7] {UD} Yes, this is ok. There can be several kinds of unresolved
symbols:
* magic symbols automatically generated by the linker. Names are
often like __start_* and __stop_*
* symbols starting with _dl_* come from the dynamic linker
* symbols resolved by using libgcc.a
(__udivdi3, __umoddi3, or similar)
* weak symbols, which need not be resolved at all
(currently fabs among others; this gets resolved if the program
is linked against libm, too.)
Generally, you should make sure you find a real program which produces
errors while linking before deciding there is a problem.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q8] ``Can I replace the libc on my Linux system with GNU libc?''
[A8] {UD} You cannot replace any existing libc for Linux with GNU
libc. There are different versions of C libraries and you can run
libcs with different major version independently.
For Linux there are today two libc versions:
libc-4 old a.out libc
libc-5 current ELF libc
GNU libc will have the major number 6 and therefore you can have this
additionally installed. For more information consult documentation for
shared library handling. The Makefiles of GNU libc will automatically
generate the needed symbolic links which the linker will use.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q9] ``I expect GNU libc to be 100% source code compatible with
the old Linux based GNU libc. Why isn't it like this?''
[A9] {DMT,UD} Not every extension in Linux libc's history was well
thought-out. In fact it had a lot of problems with standards compliance
and with cleanliness. With the introduction of a new version number these
errors now can be corrected. Here is a list of the known source code
incompatibilities:
* _GNU_SOURCE: glibc does not automatically define _GNU_SOURCE. Thus,
if a program depends on GNU extensions or some other non-standard
functionality, it is necessary to compile it with C compiler option
-D_GNU_SOURCE, or better, to put `#define _GNU_SOURCE' at the beginning
of your source files, before any C library header files are included.
This difference normally manifests itself in the form of missing
prototypes and/or data type definitions. Thus, if you get such errors,
the first thing you should do is try defining _GNU_SOURCE and see if
that makes the problem go away.
For more information consult the file `NOTES' part of the GNU C
library sources.
* reboot(): GNU libc sanitizes the interface of reboot() to be more
compatible with the interface used on other OSes. In particular,
reboot() as implemented in glibc takes just one argument. This argument
corresponds to the third argument of the Linux reboot system call.
That is, a call of the form reboot(a, b, c) needs to be changed into
reboot(c).
Beside this the header <sys/reboot.h> defines the needed constants
for the argument. These RB_* constants should be used instead of the
cryptic magic numbers.
* swapon(): the interface of this function didn't changed, but the
prototype is in a separate header file <sys/swap.h>. For the additional
argument of swapon() you should use the SWAP_* constants from
<linux/swap.h>, which get defined when <sys/swap.h> is included.
* errno: If a program uses variable "errno", then it _must_ include header
file <errno.h>. The old libc often (erroneously) declared this variable
implicitly as a side-effect of including other libc header files. glibc
is careful to avoid such namespace pollution, which, in turn, means that
you really need to include the header files that you depend on. This
difference normally manifests itself in the form of the compiler
complaining about the references of the undeclared symbol "errno".
* Linux-specific syscalls: All Linux system calls now have appropriate
library wrappers and corresponding declarations in various header files.
This is because the syscall() macro that was traditionally used to
work around missing syscall wrappers are inherently non-portable and
error-prone. The following tables lists all the new syscall stubs,
the header-file declaring their interface and the system call name.
syscall name: wrapper name: declaring header file:
------------- ------------- ----------------------
bdflush bdflush <sys/kdaemon.h>
create_module create_module <sys/module.h>
delete_module delete_module <sys/module.h>
get_kernel_syms get_kernel_syms <sys/module.h>
init_module init_module <sys/module.h>
syslog ksyslog_ctl <sys/klog.h>
* lpd: Older versions of lpd depend on a routine called _validuser().
The library does not provide this function, but instead provides
__ivaliduser() which has a slightly different interfaces. Simply
upgrading to a newer lpd should fix this problem (e.g., the 4.4BSD
lpd is known to be working).
* resolver functions/BIND: like on many other systems the functions of
the resolver library are not included in the libc itself. There is
a separate library libresolv. If you find some symbols starting with
`res_*' undefined simply add -lresolv to your call of the linker.
* the `signal' function's behaviour corresponds to the BSD semantic and
not the SysV semantic as it was in libc-5. The interface on all GNU
systems shall be the same and BSD is the semantic of choice. To use
the SysV behaviour simply use `sysv_signal'. The major difference is
that the SysV implementation sets the SA_ONESHOT flag and so the handler
gets removed after the first call.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q10] ``Why does getlogin() always return NULL on my Linux box?''
[A10] {UD} The GNU C library has a format for the UTMP and WTMP file
which differs from what your system currently has. It was extended to
fulfill the needs of the next years when IPv6 is introduced. So the
record size is different, fields might have a different position and
so reading the files written by functions from the one library cannot
be read by functions from the other library. Sorry, but this is what
a major release is for. It's better to have a cut now than having no
means to support the new techniques later.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q11] ``Where are the DST_* constants found in <sys/time.h> on many
systems?''
[A11] {UD} These constants come from the old BSD days and are not used
today anymore (even the Linux based glibc does not implement the handling
although the constants are defined).
Instead GNU libc contains the zone database handling and compatibility
code for POSIX TZ environment variable handling.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q12] ``The `gencat' utility cannot process the input which are
successfully used on my Linux libc based system. Why?''
[A12] {UD} Unlike the author of the `gencat' program which is distributed
with Linux libc I have read the underlying standards before writing the
code. It is completely compatible with the specification given in
X/Open Portability Guide.
To ease the transition from the Linux version some of the non-standard
features are also present in the `gencat' program of GNU libc. This
mainly includes the use of symbols for the message number and the automatic
generation of header files which contain the needed #defines to map the
symbols to integers.
Here is a simple SED script to convert at least some Linux specific
catalog files to the XPG4 form:
-----------------------------------------------------------------------
# Change catalog source in Linux specific format to standard XPG format.
# Ulrich Drepper <drepper@cygnus.com>, 1996.
#
/^\$ #/ {
h
s/\$ #\([^ ]*\).*/\1/
x
s/\$ #[^ ]* *\(.*\)/\$ \1/
}
/^# / {
s/^# \(.*\)/\1/
G
s/\(.*\)\n\(.*\)/\2 \1/
}
-----------------------------------------------------------------------
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q13] ``How do I configure GNU libc so that the essential libraries
like libc.so go into /lib and the other into /usr/lib?''
[A13] {UD,AJ} Like all other GNU packages GNU libc is configured to
use a base directory and install all files relative to this. If you
intend to really use GNU libc on your system this base directory is
/usr. I.e., you run
configure --prefix=/usr <other_options>
Some systems like Linux have a filesystem standard which makes a
difference between essential libraries and others. Essential
libraries are placed in /lib because this directory is required to be
located on the same disk partition as /. The /usr subtree might be
found on another partition/disk.
To install the essential libraries which come with GNU libc in /lib
one must explicitly tell this (except on Linux, see below). Autoconf
has no option for this so you have to use the file where all user
supplied additional information should go in: `configparms' (see the
`INSTALL' file). Therefore the `configparms' file should contain:
slibdir=/lib
sysconfdir=/etc
The first line specifies the directory for the essential libraries,
the second line the directory for file which are by tradition placed
in a directory named /etc.
No rule without an exception: If you configure for Linux with
--prefix=/usr, then slibdir and sysconfdir will automatically be
defined as stated above.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q14] ``When linking with the new libc I get unresolved symbols
`crypt' and `setkey'. Why aren't these functions in the
libc anymore?''
[A14] {UD} Remember the US restrictions of exporting cryptographic
programs and source code. Until this law gets abolished we cannot
ship the cryptographic function together with the libc.
But of course we provide the code and there is an very easy way to use
this code. First get the extra package. People in the US may get it
from the same place they got the GNU libc from. People outside the US
should get the code from ftp://ftp.ifi.uio.no/pub/gnu, or another
archive site outside the USA. The README explains how to install the
sources.
If you already have the crypt code on your system the reason for the
failure is probably that you failed to link with -lcrypt. The crypto
functions are in a separate library to make it possible to export GNU
libc binaries from the US.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q15] ``What are these `add-ons'?''
[A15] {UD} To avoid complications with export rules or external source
code some optional parts of the libc are distributed as separate
packages (e.g., the crypt package, see Q14).
To ease the use as part of GNU libc the installer just has to unpack
the package and tell the configuration script about these additional
subdirectories using the --enable-add-ons option. When you add the
crypt add-on you just have to use
configure --enable-add-ons=crypt,XXX ...
where XXX are possible other add-ons and ... means the rest of the
normal option list.
You can use add-ons also to overwrite some files in glibc. The add-on
system dependent subdirs are search first. It is also possible to add
banner files (use a file named `Banner') or create shared libraries.
Using add-ons has the big advantage that the makefiles of the GNU libc
can be used. Only some few stub rules must be written to get
everything running. Even handling of architecture dependent
compilation is provided. The GNU libc's sysdeps/ directory shows how
to use this feature.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q16] ``When I use GNU libc on my Linux system by linking against
to libc.so which comes with glibc all I get is a core dump.''
[A16] {UD} It is not enough to simply link against the GNU libc
library itself. The GNU C library comes with its own dynamic linker
which really conforms to the ELF API standard. This dynamic linker
must be used.
Normally this is done by the compiler. The gcc will use
-dynamic-linker /lib/ld-linux.so.1
unless the user specifies her/himself a -dynamic-linker argument. But
this is not the correct name for the GNU dynamic linker. The correct
name is /lib/ld.so.1 which is the name specified in the SVr4 ABi.
To change your environment to use GNU libc for compiling you need to
change the `specs' file of your gcc. This file is normally found at
/usr/lib/gcc-lib/<arch>/<version>/specs
In this file you have to change a few things:
- change `ld-linux.so.1' to `ld.so.1' (or to ld-linux.so.2, see below)
- remove all expression `%{...:-lgmon}'; there is no libgmon in glibc
Things are getting a bit more complicated if you have GNU libc
installed in some other place than /usr, i.e., if you do not want to
use it instead of the old libc. In this case the needed startup files
and libraries are not found in the regular places. So the specs file
must tell the compiler and linker exactly what to use. Here is for
example the gcc-2.7.2 specs file when GNU libc is installed at
/usr:
-----------------------------------------------------------------------
*asm:
%{V} %{v:%{!V:-V}} %{Qy:} %{!Qn:-Qy} %{n} %{T} %{Ym,*} %{Yd,*} %{Wa,*:%*}
*asm_final:
%{pipe:-}
*cpp:
%{fPIC:-D__PIC__ -D__pic__} %{fpic:-D__PIC__ -D__pic__} %{!m386:-D__i486__} %{posix:-D_POSIX_SOURCE} %{pthread:-D_REENTRANT}
*cc1:
%{profile:-p}
*cc1plus:
*endfile:
%{!shared:crtend.o%s} %{shared:crtendS.o%s} crtn.o%s
*link:
-m elf_i386 %{shared:-shared} %{!shared: %{!ibcs: %{!static: %{rdynamic:-export-dynamic} %{!dynamic-linker:-dynamic-linker /lib/ld-linux.so.2}} %{static:-static}}}
*lib:
%{!shared: %{pthread:-lpthread} %{profile:-lc_p} %{!profile: -lc}}
*libgcc:
-lgcc
*startfile:
%{!shared: %{pg:gcrt1.o%s} %{!pg:%{p:gcrt1.o%s} %{!p:%{profile:gcrt1.o%s} %{!profile:crt1.o%s}}}} crti.o%s %{!shared:crtbegin.o%s} %{shared:crtbeginS.o%s}
*switches_need_spaces:
*signed_char:
%{funsigned-char:-D__CHAR_UNSIGNED__}
*predefines:
-D__ELF__ -Dunix -Di386 -Dlinux -Asystem(unix) -Asystem(posix) -Acpu(i386) -Amachine(i386)
*cross_compile:
0
*multilib:
. ;
-----------------------------------------------------------------------
The above is currently correct for ix86/Linux. Because of
compatibility issues on this platform the dynamic linker must have
a different name: ld-linux.so.2. So you have to replace
%{!dynamic-linker:-dynamic-linker=/home/gnu/lib/ld-linux.so.2}
by
%{!dynamic-linker:-dynamic-linker=/home/gnu/lib/ld.so.1}
in the above example specs file to make it work for other systems.
Version 2.7.2.3 does and future versions of GCC will automatically
provide the correct specs.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q17] ``Looking through the shared libc file I haven't found the
functions `stat', `lstat', `fstat', and `mknod' and while
linking on my Linux system I get error messages. How is
this supposed to work?''
[A17] {RM} Believe it or not, stat and lstat (and fstat, and mknod)
are supposed to be undefined references in libc.so.6! Your problem is
probably a missing or incorrect /usr/lib/libc.so file; note that this
is a small text file now, not a symlink to libc.so.6. It should look
something like this:
GROUP ( libc.so.6 ld.so.1 libc.a )
or in ix86/Linux and alpha/Linux:
GROUP ( libc.so.6 ld-linux.so.2 libc.a )
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q18] ``The prototypes for `connect', `accept', `getsockopt',
`setsockopt', `getsockname', `getpeername', `send',
`sendto', and `recvfrom' are different in GNU libc from
any other system I saw. This is a bug, isn't it?''
[A18] {UD} No, this is no bug. This version of the GNU libc already
follows the Single Unix specifications (and I think the POSIX.1g
draft which adopted the solution). The type for parameter describing
a size is now `socklen_t', a new type.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q19] ``My XXX kernel emulates a floating-point coprocessor for me.
Should I enable --with-fp?''
[A19] {UD} As `configure --help' shows the default value is `yes' and
this should not be changed unless the FPU instructions would be
invalid. I.e., an emulated FPU is for the libc as good as a real one.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q20] ``How can I compile gcc 2.7.2.1 from the gcc source code using
glibc 2.x?
[A20] {AJ} There's only correct support for glibc 2.0.x in gcc 2.7.2.3
or later. You should get at least gcc 2.7.2.3. All previous versions
had problems with glibc support.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q21] ``On Linux I've got problems with the declarations in Linux
kernel headers.''
[A21] {UD,AJ} On Linux, the use of kernel headers is reduced to a very
minimum. Besides giving Linus the possibility to change the headers
more freely it has another reason: user level programs now do not
always use the same types like the kernel does.
I.e., the libc abstracts the use of types. E.g., the sigset_t type is
in the kernel 32 or 64 bits wide. In glibc it is 1024 bits wide, in
preparation for future development. The reasons are obvious: we don't
want to have a new major release when the Linux kernel gets these
functionality. Consult the headers for more information about the changes.
Therefore you shouldn't include Linux kernel header files directly if
glibc has defined a replacement. Otherwise you might get undefined
results because of type conflicts.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q22] ``When I try to compile code which uses IPv6 header and
definitions on my Linux 2.x.y system I am in trouble.
Nothing seems to work.''
[A22] {UD} The problem is that the IPv6 development still has not reached
a point where it is stable. There are still lots of incompatible changes
made and the libc headers have to follow.
Currently (as of 970401) according to Philip Blundell <philb@gnu.ai.mit.edu>
the required kernel version is 2.1.30.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q23] ``When compiling GNU libc I get lots of errors saying functions
in glibc are duplicated in libgcc.''
[A23] {EY} This is *exactly* the same problem that I was having. The
problem was due to the fact that the autoconfigure didn't correctly
detect that linker flag --no-whole-archive was supported in my linker.
In my case it was because I had run ./configure with bogus CFLAGS, and
the test failed.
One thing that is particularly annoying about this problem is that
once this is misdetected, running configure again won't fix it unless
you first delete config.cache.
{UD} Starting with glibc-2.0.3 there should be a better test to avoid
some problems of this kind. The setting of CFLAGS is checked at the
very beginning and if it is not usable `configure' will bark.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q24] ``I have set up /etc/nis.conf, and the Linux libc 5 with NYS
works great. But the glibc NIS+ doesn't seem to work.''
[A24] The glibc NIS+ implementation uses a /var/nis/NIS_COLD_START
file for storing information about the NIS+ server and their public
keys, because the nis.conf file do not contain all necessary
information. You have to copy a NIS_COLD_START file from a Solaris
client (the NIS_COLD_START file is byte order independend) or generate
it new with nisinit from the nis-tools (look at
http://www-vt.uni-paderborn.de/~kukuk/linux/nisplus.html).
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q25] ``After installing glibc name resolving doesn't work properly.''
[A25] {AJ} You probable should read the manual section describing
``nsswitch.conf'' (just type `info libc "NSS Configuration File"').
The NSS configuration file is usually the culprit.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
[Q26] ``I have /usr/include/net and /usr/include/scsi as symlinks
into my Linux source tree. Is that wrong?''
[A26] {PB} This was necessary for libc5, but is not correct when using
glibc. Including the kernel header files directly in user programs
usually does not work (see Q21). glibc provides its own <net/*> and
<scsi/*> header files to replace them, and you may have to remove any
symlink that you have in place before you install glibc. However,
/usr/include/asm and /usr/include/linux should remain as they were.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
Answers were given by:
{UD} Ulrich Drepper, <drepper@cygnus.com>
{DMT} David Mosberger-Tang, <davidm@AZStarNet.com>
{RM} Roland McGrath, <roland@gnu.ai.mit.edu>
{HJL} H.J. Lu, <hjl@gnu.ai.mit.edu>
{AJ} Andreas Jaeger, <aj@arthur.rhein-neckar.de>
{EY} Eric Youngdale, <eric@andante.jic.com>
{PB} Phil Blundell, <Philip.Blundell@pobox.com>
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