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authorUlrich Drepper <drepper@redhat.com>1996-11-06 04:24:40 +0000
committerUlrich Drepper <drepper@redhat.com>1996-11-06 04:24:40 +0000
commit2c6fe0bd3b270fc644dd4c773f2d47b93f404efe (patch)
treea578bcc93bbeaafacb6012213c458e33b7907528 /manual/arith.texi
parentf5311448f83eada5c5cabf55aae2619dcb1869c0 (diff)
update from main archive 961105cvs/libc-961106
Wed Nov 6 04:30:26 1996 Ulrich Drepper <drepper@cygnus.com> * sysdeps/unix/sysv/linux/syscalls.list: Add weak alias llseek for _llseek syscall. Reported by Andy Sewell <puck@pookhill.demon.co.uk>. * string/argz.h: Don't protect by __USE_GNU. Tue Nov 5 23:38:28 1996 Ulrich Drepper <drepper@cygnus.com> * Lots of files: Update and reformat copyright. * Makefile (headers): Add xopen_lim.h. * catgets/nl_types.h: Move __BEGIN_DECLS before definition of nl_catd. * grp/grp.h: Define setgrent, getgrent, endgrent, and getgrent_r if __USE_XOPEN_EXTENDED is defined. * pwd/pwd.h: Define setpwent, getpwent, endpwent, and getpwent_r if __USE_XOPEN_EXTENDED is defined. * io/Makefile (routines): Add lchown. * io/sys/poll.h: Add definition of POLLWRNORM. * io/sys/stat.h: Declare lstat, fchmod, mknod when __USE_XOPEN_EXTENDED is defined. * libio/Makefile (routines): Add obprintf. * libio/obprintf.c: New file. * libio/iolibio.h: Add prototypes for _IO_obstack_vprintf and _IO_obstack_printf. * libio/libio.h: Fix typo. * libio/stdio.h: Declare tempnam if __USE_XOPEN_EXTENDED is defined. Add prototypes for obstack_vprintf and obstack_printf. * manual/creature.texi: Describe _XOPEN_SOURCE macro. * manual/intro.texi: Add reference to NSS chapter. * manual/libc.texinfo: Update UPDATED. Comment out `@printindex cp'. It works again. * manual/memory.texi: Add description for obstack_ptr_grow, obstack_int_grow, obstack_ptr_grow_fast, and obstack_int_grow_fast. * manual/nss.texi: Add a few @cindex entries and change NSS_STATUS_* index entries to @vindex. * manual/users.texi: Correct @cindex entry for Netgroup. * math/mathcalls.h: Use __USE_XOPEN and __USE_XOPEN_EXTENDED to make declarations visible for X/Open sources. * misc/search.h: Declare insque/remque only is __USE_SVID or __USE_XOPEN_EXTENDED is defined. * misc/sys/uio.h (readv, writev): Change return value from int to ssize_t. * posix/Makefile (headers): Add re_comp.h. * posix/re_comp.h: New file. XPG interface to regex functions. * posix/getconf.c: Add all names from XPG4.2. * posix/posix1_lim.h: Increase minimum values for _POSIX_CHILD_MAX and _POSIX_OPEN_MAX to minimums from XPG4.2. * sysdeps/generic/confname.h: Add all _SC_* names from XPG4.2. * sysdeps/posix/sysconf.c: Handle new _SC_* values. * sysdeps/stub/sysconf.c: Likewise. * posix/unistd.h: Add declaration of ualarm and lchown. Declare usleep, fchown, fchdir, nice, getpgid, setsid, getsid, setreuid, setregid, vfork, ttyslot, symlink, readlink, gethostid, truncate, ftruncate, getdtablesize, brk, sbrk, lockf when __USE_XOPEN_EXTENDED is defined. * posix/sys/wait.h: Declare wait3 if __USE_XOPEN_EXTENDED is defined. * shadow/shadow.h: Define SHADOW using _PATH_SHADOW. * sysdeps/generic/paths.h: Define _PATH_SHADOW. * sysdeps/unix/sysv/linux/paths.h: Likewise. * signal/signal.h: Declare killpg, sigstack and sigaltstack when __USE_XOPEN_EXTENDED is defined. * stdio/stdio.h: Declare tempnam when __USE_XOPEN is defined. * stdlib/stdlib.h: Make rand48 functions available when __USE_XOPEN is defined. Likewise for valloc, putenv, realpath, [efg]cvt*, and getsubopt functions. * string/string.h: Make memccpy, strdup, bcmp, bcopy, bzero, index, and rindex available when __USE_XOPEN_EXTENDED is defined. * sysdeps/mach/getpagesize.c: De-ANSI-fy. Change return type to int. * sysdeps/posix/getpagesize.c: Likewise. * sysdeps/stub/getpagesize.c: Likewise. * sysdeps/unix/getpagesize.c: Likewise. * time/africa: Update from tzdata1996l. * time/asia: Likewise. * time/australia: Likewise. * time/europe: Likewise. * time/northamerica: Likewise. * time/pacificnew: Likewise. * time/southamerica: Likewise. * time/tzfile.h: Update from tzcode1996m. * time/time.h: Declare strptime if __USE_XOPEN. Declare daylight and timezone also if __USE_XOPEN. * time/sys/time.h: Remove declaration of ualarm. * wctype/wctype.h: Just reference ISO C standard. Tue Nov 5 01:26:32 1996 Richard Henderson <rth@tamu.edu> * crypt/Makefile: Add crypt routines to libc as well iff $(crypt-in-libc) is set. Do this for temporary binary compatibility on existing Linux/Alpha installations. * stdlib/div.c, sysdeps/generic/div.c: Move file to .../generic/. * stdlib/ldiv.c, sysdeps/generic/ldiv.c: Likewise. * stdlib/lldiv.c, sysdeps/generic/lldiv.c: Likewise. * sysdeps/alpha/Makefile (divrem): Add divlu, dviqu, remlu, and remqu. * sysdeps/alpha/div.S: New file. * sysdeps/alpha/ldiv.S: New file. * sysdeps/alpha/lldiv.S: New file. * sysdeps/alpha/divrem.h: Merge signed and unsigned division. Take pointers from Linus and tighten the inner loops a bit. * sysdeps/alpha/divl.S: Change defines for merged routines. * sysdeps/alpha/divq.S: Likewise. * sysdeps/alpha/reml.S: Likewise. * sysdeps/alpha/remq.S: Likewise. * sysdeps/alpha/divlu.S: Remove file. * sysdeps/alpha/divqu.S: Likewise. * sysdeps/alpha/remlu.S: Likewise. * sysdeps/alpha/remqu.S: Likewise. * sysdeps/alpha/bsd-_setjmp.S: If PROF, call _mcount. * sysdeps/alpha/bsd-setjmp.S: Likewise. * sysdeps/alpha/bzero.S: Likewise. * sysdeps/alpha/ffs.S: Likewise. * sysdeps/alpha/htonl.S: Likewise. * sysdeps/alpha/htons.S: Likewise. * sysdeps/alpha/memchr.S: Likewise. * sysdeps/alpha/memset.S: Likewise. * sysdeps/alpha/s_copysign.S: Likewise. * sysdeps/alpha/s_fabs.S: Likewise. * sysdeps/alpha/setjmp.S: Likewise. * sysdeps/alpha/stpcpy.S: Likewise. * sysdeps/alpha/stpncpy.S: Likewise. * sysdeps/alpha/strcat.S: Likewise. * sysdeps/alpha/strchr.S: Likewise. * sysdeps/alpha/strcpy.S: Likewise. * sysdeps/alpha/strlen.S: Likewise. * sysdeps/alpha/strncat.S: Likewise. * sysdeps/alpha/strncpy.S: Likewise. * sysdeps/alpha/strrchr.S: Likewise. * sysdeps/alpha/udiv_qrnnd.S: Likewise. Fix private labels. Convert two small jumps to use conditional moves. * sysdeps/unix/alpha/sysdep.h: Compress all __STDC__ nastiness. (PSEUDO): If PROF, call _mcount. * sysdeps/unix/sysv/linux/alpha/brk.S: If PROF, call _mcount. * sysdeps/unix/sysv/linux/alpha/clone.S: Likewise. * sysdeps/unix/sysv/linux/alpha/ieee_get_fp_control.S: Likewise. * sysdeps/unix/sysv/linux/alpha/ieee_set_fp_control.S: Likewise. * sysdeps/unix/sysv/linux/alpha/llseek.S: Likewise. * sysdeps/unix/sysv/linux/alpha/sigsuspend.S: Likewise. * sysdeps/unix/sysv/linux/alpha/syscall.S: Likewise. * sysdeps/alpha/memcpy.S: New file. Odd layout because it should eventually contain memmove as well. * sysdeps/alpha/strcmp.S: New file. * sysdeps/alpha/strncmp.S: New file. * sysdeps/alpha/w_sqrt.S: New file. Tue Nov 5 18:06:06 1996 Ulrich Drepper <drepper@cygnus.com> * sysdeps/mach/hurd/ttyname_r.c: Use `size_t' for len variable. Tue Nov 5 12:09:29 1996 Ulrich Drepper <drepper@cygnus.com> * sysdep/generic/sysdep.h: Define END only if not yet defined. * sysdep/unix/sysdep.h: Define PSEUDO_END only if not yet defined. Reported by Thomas Bushnell, n/BSG. Mon Nov 4 22:46:53 1996 Ulrich Drepper <drepper@cygnus.com> * manual/users.texi (Netgroup Data): Remove { } around @cindex. Mon Nov 4 19:07:05 1996 Ulrich Drepper <drepper@cygnus.com> * malloc/calloc.c: Check for overflow before trying to allocate memory. Proposed by Neil Matthews <nm@adv.sbc.sony.co.jp>. Fri Nov 1 18:18:32 1996 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * manual/llio.texi (Operating Modes): Add missing arguments to @deftypevr in O_NONBLOCK description. * manual/time.texi (Time Zone Functions): Enclose type name in braces in description of tzname. FIXME: this does not yet work correctly in info. Sun Nov 3 17:29:06 1996 Ulrich Drepper <drepper@cygnus.com> * features.h: Add X/Open macros. * posix/unistd.h: Define X/Open macros. * sysdeps/generic/confname.h: Add _SC_XOPEN_XCU_VERSION, _SC_XOPEN_UNIX, _SC_XOPEN_CRYPT, _SC_XOPEN_ENH_I18N, _SC_XOPEN_SHM, _SC_2_CHAR_TERM, _SC_2_C_VERSION, and _SC_2_UPE. * sysdeps/posix/sysconf.c: Handle new constants. * sysdeps/stub/sysconf.c: Likewise. * sysdeps/unix/sysv/linux/posix_opt.h: Add definition of _XOPEN_SHM. * catgets/catgets.c (catopen): Set errno to ENOMEM when we run out of memory. (catgets): Set errno to EBADF when catalog handle is invalid. Set errno to ENOMSG when translation is not available. (catclose): Set errno to EBADF when catalog handle is invalid. * ctype/ctype.h: Declare isascii and toascii when __USE_XOPEN. Likewise for _toupper and _tolower. * manual/arith.texi: Document strtoq, strtoll, strtouq, strtoull, strtof, and strtold. * manual/math.texi: Document HUGE_VALf and HUGE_VALl. * manual/stdio.h: Document ' flag for numeric formats of scanf. * manual/users.texi: Document that cuserid shouldn't be used. * misc/Makefile (routines): Add dirname. (headers): Add libgen.h. (tests): Add tst-dirname. * misc/dirname.c: New file. * misc/libgen.h: New file. * misc/tst-dirname.c: New file. * misc/search.h: Parameter of hcreate must be of type size_t. * misc/hsearch.c: Likewise. * misc/hsearch_r.c: Likewise for hcreate_r. * misc/search.h: Parameters of insque and remque must be `void *'. * misc/insremque.c: Likewise. * posix/unistd.h: Move declarations of mktemp and mkstemp to... * stdlib/stdlib.h: ...here. * posix/unistd.h [__USE_XOPEN]: Add prototypes for crypt, setkey, encrypt, and swab. * stdio-common/printf-parse.h (struct printf_spec): Add pa_wchar and pa_wstring. (parse_one_spec): Remove Linux compatibility code. Recognize %C and %S formats. * stdio-common/printf.h: Add PA_WCHAR and PA_WSTRING. * stdio-common/vfprintf.c: Add implementation of %C and %S format. * stdio-common/vfscanf.c: Likewise for scanf. * stdlib/l64a.c: Return value for 0 must be the empty string. * stdlib/stdlib.h: Declare reentrant function from rand49 family only if __USE_REENTRANT. Declare rand48 functions also if __USE_XOPEN. * stdlib/strtol.c: Return 0 and set errno to EINVAL when BASE is not a legal value. Return 0 and set errno to EINVAL when strou* sees negativ number. * stdlib/tst-strtol.c: De-ANSI-fy. Change expected results for test of unsigned function and negative input. * string/stratcliff.c: Prevent warnings. * string.h: Move declaration of swab to <unistd.h>. * string/swab.c: De-ANSI-fy. * sysdeps/posix/cuserid.c: Implement using getpwuid_r. * sysdeps/posix/mkstemp.c: Include <stdlib.h> for prototype. * sysdeps/posix/mktemp.c: Likewise. * sysdeps/stub/mkstemp.c: Likewise. * sysdeps/stub/mktemp.c: Likewise. * sysvipc/sys/ipc.h: Prototypes of ftok have to be of types `const char *' and `int'. * sysvipc/ftok.c: Likewise. Make sure only lower 8 bits of PROJ_ID are used. Sun Nov 3 03:21:28 1996 Heiko Schroeder <Heiko.Schroeder@post.rwth-aachen.de> * locale/programs/ld-numeric.c (numeric_output): Compute idx[0] correctly. Sat Nov 2 17:44:32 1996 Ulrich Drepper <drepper@cygnus.com> * sysdeps/posix/cuserid.c: Use reentrant functions. * manual/users.texi: Tell that cuserid is marked to be withdrawn in XPG4.2. Sat Nov 2 14:26:37 1996 Ulrich Drepper <drepper@cygnus.com> Linus said he will make sure no system call will return a value in -1 ... -4095 as a valid result. * sysdeps/unix/sysv/linux/i386/sysdep.h: Correct test for error. * sysdeps/unix/sysv/linux/i386/syscall.S: Likewise. * sysdeps/unix/sysv/linux/m68k/sysdep.h: Likewise. * sysdeps/unix/sysv/linux/m68k/syscall.S: Likewise. Sat Nov 2 16:54:49 1996 NIIBE Yutaka <gniibe@mri.co.jp> * sysdeps/stub/lockfile.c [!USE_IN_LIBIO]: Define weak alias for __funlockfile, not a circular alias. Define __IO_ftrylockfile if USE_IN_LIBIO and __ftrylockfile if not, not vice versa. * sysdeps/unix/sysv/linux/i386/sysdep.S (__errno_location): Make it a weak symbol. * sysdeps/unix/sysv/linux/m68k/sysdep.S (__errno_location): Likewise. Likewise. * crypt/Makefile (rpath-link): Extend search path to current directory.
Diffstat (limited to 'manual/arith.texi')
-rw-r--r--manual/arith.texi126
1 files changed, 123 insertions, 3 deletions
diff --git a/manual/arith.texi b/manual/arith.texi
index b3f646a187..8ea9508e3e 100644
--- a/manual/arith.texi
+++ b/manual/arith.texi
@@ -469,7 +469,8 @@ syntax used for integer constants in C.
Otherwise @var{base} must have a value between @code{2} and @code{35}.
If @var{base} is @code{16}, the digits may optionally be preceded by
-@samp{0x} or @samp{0X}.
+@samp{0x} or @samp{0X}. If base has no legal value the value returned
+is @code{0l} and the global variable @code{errno} is set to @code{EINVAL}.
@item
Any remaining characters in the string. If @var{tailptr} is not a null
@@ -492,6 +493,11 @@ representable because of overflow, @code{strtol} returns either
appropriate for the sign of the value. It also sets @code{errno}
to @code{ERANGE} to indicate there was overflow.
+Because the value @code{0l} is a correct result for @code{strtol} the
+user who is interested in handling errors should set the global variable
+@code{errno} to @code{0} before calling this function. So it can be
+tested whether an error occured or not.
+
There is an example at the end of this section.
@end deftypefun
@@ -504,6 +510,51 @@ value with type @code{unsigned long int}. No @samp{+} or @samp{-} sign
may appear before the number, but the syntax is otherwise the same as
described above for @code{strtol}. The value returned in case of
overflow is @code{ULONG_MAX} (@pxref{Range of Type}).
+
+Like @code{strtol} this function sets @code{errno} and returns the value
+@code{0ul} in case the value for @var{base} is not in the legal range.
+For @code{strtoul} this can happen in another situation. In case the
+number to be converted is negative @code{strtoul} also sets @code{errno}
+to @code{EINVAL} and returns @code{0ul}.
+@end deftypefun
+
+@comment stdlib.h
+@comment BSD
+@deftypefun {long long int} strtoq (const char *@var{string}, char **@var{tailptr}, int @var{base})
+The @code{strtoq} (``string-to-quad-word'') function is like
+@code{strtol} except that is deals with extra long numbers and it
+returns its value with type @code{long long int}.
+
+If the string has valid syntax for an integer but the value is not
+representable because of overflow, @code{strtoq} returns either
+@code{LONG_LONG_MAX} or @code{LONG_LONG_MIN} (@pxref{Range of Type}), as
+appropriate for the sign of the value. It also sets @code{errno} to
+@code{ERANGE} to indicate there was overflow.
+@end deftypefun
+
+@comment stdlib.h
+@comment GNU
+@deftypefun {long long int} strtoll (const char *@var{string}, char **@var{tailptr}, int @var{base})
+@code{strtoll} is only an commonly used other name for the @code{strtoq}
+function. Everything said for @code{strtoq} applies to @code{strtoll}
+as well.
+@end deftypefun
+
+@comment stdlib.h
+@comment BSD
+@deftypefun {unsigned long long int} strtouq (const char *@var{string}, char **@var{tailptr}, int @var{base})
+The @code{strtouq} (``string-to-unsigned-quad-word'') function is like
+@code{strtoul} except that is deals with extra long numbers and it
+returns its value with type @code{unsigned long long int}. The value
+returned in case of overflow is @code{ULONG_LONG_MAX} (@pxref{Range of Type}).
+@end deftypefun
+
+@comment stdlib.h
+@comment GNU
+@deftypefun {unsigned long long int} strtoull (const char *@var{string}, char **@var{tailptr}, int @var{base})
+@code{strtoull} is only an commonly used other name for the @code{strtouq}
+function. Everything said for @code{strtouq} applies to @code{strtoull}
+as well.
@end deftypefun
@comment stdlib.h
@@ -523,6 +574,29 @@ value rather than @code{long int}. The @code{atoi} function is also
considered obsolete; use @code{strtol} instead.
@end deftypefun
+The POSIX locales contain some information about how to format numbers
+(@pxref{General Numeric}). This mainly deals with representing numbers
+for better readability for humans. The functions present so far in this
+section cannot handle numbers in this form.
+
+If this functionality is needed in a program one can use the functions
+from the @code{scanf} family which know about the flag @samp{'} for
+parsing numeric input (@pxref{Numeric Input Conversions}). Sometimes it
+is more desirable to have finer control.
+
+In these situation one could use the function
+@code{__strto@var{XXX}_internal}. @var{XXX} here stands for any of the
+above forms. All numeric conversion functions (including the functions
+to process floating-point numbers) have such a counterpart. The
+difference to the normal for is the extra argument at the end of the
+parameter list. If this value has an non-zero value the handling of
+number grouping is enabled. The advantage from using these functions is
+that the @var{tailptr} parameters allow to determine which part of the
+input is processed. The @code{scanf} functions don't provide this
+information. The drawback of using these functions is that they are not
+portable. They only exist in the GNU C library.
+
+
Here is a function which parses a string as a sequence of integers and
returns the sum of them:
@@ -604,8 +678,8 @@ number, no conversion is performed. In this case, @code{strtod} returns
a value of zero and the value returned in @code{*@var{tailptr}} is the
value of @var{string}.
-In a locale other than the standard @code{"C"} locale, this function may
-recognize additional locale-dependent syntax.
+In a locale other than the standard @code{"C"} or @code{"POSIX"} locale,
+this function may recognize additional locale-dependent syntax.
If the string has valid syntax for a floating-point number but the value
is not representable because of overflow, @code{strtod} returns either
@@ -613,9 +687,55 @@ positive or negative @code{HUGE_VAL} (@pxref{Mathematics}), depending on
the sign of the value. Similarly, if the value is not representable
because of underflow, @code{strtod} returns zero. It also sets @code{errno}
to @code{ERANGE} if there was overflow or underflow.
+
+Since the value zero which is returned in the error case is also a valid
+result the user should set the global variable @code{errno} to null
+before calling this function. So one can test for failures after the
+call since all failures set @code{errno} to a non-zero value.
@end deftypefun
@comment stdlib.h
+@comment GNU
+@deftypefun float strtof (const char *@var{string}, char **@var{tailptr})
+This function is similar to the @code{strtod} function but it returns a
+@code{float} value instead of a @code{double} value. If the precision
+of a @code{float} value is sufficent this function should be used since
+it is much faster than @code{strtod} on some architectures. The reasons
+are obvious: @w{IEEE 754} defines @code{float} to have a mantissa of 23
+bits while @code{double} has 53 bits and every additional bit of
+precision can require additional computation.
+
+If the string has valid syntax for a floating-point number but the value
+is not representable because of overflow, @code{strtof} returns either
+positive or negative @code{HUGE_VALf} (@pxref{Mathematics}), depending on
+the sign of the value.
+
+This function is a GNU extension.
+@end deftypefun
+
+@comment stdlib.h
+@comment GNU
+@deftypefun {long double} strtold (const char *@var{string}, char **@var{tailptr})
+This function is similar to the @code{strtod} function but it returns a
+@code{long double} value instead of a @code{double} value. It should be
+used when high presision is used. On systems which define a @code{long
+double} type (i.e., on which it is not the same as @code{double})
+running this function might take significently more time since more bits
+of precision are required.
+
+If the string has valid syntax for a floating-point number but the value
+is not representable because of overflow, @code{strtold} returns either
+positive or negative @code{HUGE_VALl} (@pxref{Mathematics}), depending on
+the sign of the value.
+
+This function is a GNU extension.
+@end deftypefun
+
+As for the integer parsing functions there are additional functions
+which will handle numbers represented using the grouping scheme of the
+current locale (@pxref{Parsing of Integers}).
+
+@comment stdlib.h
@comment ANSI
@deftypefun double atof (const char *@var{string})
This function is similar to the @code{strtod} function, except that it