Hello Motohiro, On Thu, Feb 18, 2010 at 5:19 AM, KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> wrote: > Hi Michael, > > I recently found little mismatch between the impmentation and the man in > atanh function. > > current man page says > http://www.kernel.org/doc/man-pages/online/pages/man3/atanh.3.html > > --------------------------------------------------------- > BUGS > For a pole error, errno is set to EDOM; POSIX.1 says it should be set to > ERANGE. > --------------------------------------------------------- > > but following test programs "34: Numerical result out of range". > It mean atanh return ERANGE rightly. > > > atanh_test.c > --------------------------------------------------------- > #include <math.h> > #include <stdio.h> > #include <sys/errno.h> > #include <string.h> > > int main(void) > { > double d; > > d = atanh(1.0); > if (d == HUGE_VAL) > printf("huge %d: %s\n", errno, strerror(errno)); > else > printf("Oops no error\n"); > > return 0; > } > --------------------------------------------------------- > > > I dug in glibc's ChangeLog and I found following change. > So, can we consider to change the man too? > > > --------------------------------------------------------- > 2009-04-26 Ulrich Drepper <drepper@xxxxxxxxxx> > > * sysdeps/ieee754/dbl-64/s_expm1.c: Set errno for overflow. > * sysdeps/ieee754/flt-32/s_expm1f.c: Likewise. > * sysdeps/x86_64/fpu/s_expm1l.S: Likewise. > > * sysdeps/ieee754/k_standard.c (__kernel_standard): Pole errors in > atanh should set ERANGE. Thanks for your detailed report. I applied the following change for man-pages-2.37. Cheers, Michael --- a/man3/atanh.3 +++ b/man3/atanh.3 @@ -129,16 +129,16 @@ The variant returning also conforms to SVr4, 4.3BSD, C89. .SH BUGS -For a pole error, -.\" -.\" FIXME . this is as at glibc 2.8; check later if this bug is fixed +In glibc 2.9 and earlier, +.\" Bug: http://sources.redhat.com/bugzilla/show_bug.cgi?id=6759 .\" This can be seen in sysdeps/ieee754/k_standard.c -.\" Bug raised: http://sources.redhat.com/bugzilla/show_bug.cgi?id=6759 +when a pole error occurs, .I errno -is set to -.BR EDOM ; -POSIX.1 says it should be set to +as set to +.BR EDOM +instead of the POSIX-mandated .BR ERANGE . +Since version 2.10, glibc does the right thing. .SH "SEE ALSO" .BR acosh (3), .BR asinh (3), -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Author of "The Linux Programming Interface"; http://man7.org/tlpi/ -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
