view doc/posix-functions/vprintf.texi @ 14823:3fe3b9fc9c12

docs: document recently fixed glibc printf bug Document it as a known bug, but one where we don't provide a workaround since programmers are unlikely to hit it in practice. * doc/posix-functions/fprintf.texi (fprintf): Document it. * doc/posix-functions/printf.texi (printf): Likewise. * doc/posix-functions/vfprintf.texi (vfprintf): Likewise. * doc/posix-functions/vprintf.texi (vprintf): Likewise. Signed-off-by: Eric Blake <eblake@redhat.com>
author Eric Blake <eblake@redhat.com>
date Tue, 24 May 2011 17:33:39 -0600
parents 4e83bc0de9e4
children 805e07cd88c7
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@node vprintf
@section @code{vprintf}
@findex vprintf

POSIX specification:@* @url{http://www.opengroup.org/onlinepubs/9699919799/functions/vprintf.html}

Gnulib module: vprintf-posix or stdio, nonblocking, sigpipe

Portability problems fixed by Gnulib module @code{vprintf-posix}:
@itemize
@item
This function does not support size specifiers as in C99 (@code{hh}, @code{ll},
@code{j}, @code{t}, @code{z}) on some platforms:
AIX 5.1, HP-UX 11.23, IRIX 6.5, OSF/1 5.1, Solaris 9, Cygwin 1.5.24, mingw, BeOS.
@item
printf of @samp{long double} numbers is unsupported on some platforms:
mingw, BeOS.
@item
printf @code{"%f"}, @code{"%e"}, @code{"%g"} of Infinity and NaN yields an
incorrect result on some platforms:
AIX 5.2, OSF/1 5.1, Solaris 11 2010-11, mingw.
@item
This function does not support the @samp{a} and @samp{A} directives on some
platforms:
glibc-2.3.6, MacOS X 10.5, NetBSD 5.0, OpenBSD 4.0, AIX 5.2, HP-UX 11,
IRIX 6.5, OSF/1 5.1, Solaris 11 2010-11, Cygwin 1.5.x, mingw, BeOS.
@item
This function does not support the @samp{F} directive on some platforms:
NetBSD 3.0, AIX 5.1, HP-UX 11.23, IRIX 6.5, OSF/1 5.1, Solaris 9,
Cygwin 1.5.x, mingw, BeOS.
@item
This function does not support the @samp{ls} directive on some platforms:
OpenBSD 4.0, IRIX 6.5, Solaris 2.6, Cygwin 1.5.x, Haiku.
@item
This function does not support precisions in the @samp{ls} directive correctly
on some platforms:
Solaris 11 2010-11.
@item
This function does not support format directives that access arguments in an
arbitrary order, such as @code{"%2$s"}, on some platforms:
NetBSD 3.0, mingw, BeOS.
@item
This function doesn't support the @code{'} flag on some platforms:
NetBSD 3.0, Cygwin 1.5.24, mingw.
@item
This function behaves incorrectly when a @samp{-} flag and a negative width
are specified together, on some platforms:
HP-UX 10.20.
@item
printf @code{"%010f"} of NaN and Infinity yields an incorrect result (padded
with zeroes) on some platforms:
MacOS X 10.5, FreeBSD 6.0, NetBSD 5.0, AIX 5.2, IRIX 6.5, OSF/1 5.1, Solaris 11 2010-11, Cygwin 1.5.x, mingw.
@item
This function does not support precisions larger than 512 or 1024 in integer,
floating-point and pointer output on some platforms:
Solaris 10/x86, mingw, BeOS.
@item
This function mishandles large floating point precisions
(for example, formatting 1.0 with @samp{"%.511f"})
on some platforms:
Solaris 10.
@item
This function can crash in out-of-memory conditions on some platforms:
MacOS X 10.3, FreeBSD 6.0, NetBSD 5.0.
@end itemize

Portability problems fixed by Gnulib module @code{stdio} or @code{vprintf-posix}, together with module @code{nonblocking}:
@itemize
@item
When writing to a non-blocking pipe whose buffer is full, this function fails
with @code{errno} being set to @code{ENOSPC} instead of @code{EAGAIN} on some
platforms:
mingw.
@end itemize

Portability problems fixed by Gnulib module @code{stdio} or @code{vprintf-posix}, together with module @code{sigpipe}:
@itemize
@item
When writing to a pipe with no readers, this function fails, instead of
obeying the current @code{SIGPIPE} handler, on some platforms:
mingw.
@end itemize

Portability problems not fixed by Gnulib:
@itemize
@item
Attempting to write to a read-only stream fails with @code{EOF} but
does not set the error flag for @code{ferror} on some platforms:
glibc 2.13.
@end itemize