Differential D6302 Diff 16124 lib/libc/stdio/printf.3

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lib/libc/stdio/printf.3

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.Os		.Os
.Sh NAME		.Sh NAME
.Nm printf , fprintf , sprintf , snprintf , asprintf , dprintf ,		.Nm printf , fprintf , sprintf , snprintf , asprintf , dprintf ,
.Nm vprintf , vfprintf, vsprintf , vsnprintf , vasprintf, vdprintf		.Nm vprintf , vfprintf, vsprintf , vsnprintf , vasprintf, vdprintf
.Nd formatted output conversion		.Nd formatted output conversion
.Sh LIBRARY		.Sh LIBRARY
.Lb libc		.Lb libc
.Sh SYNOPSIS		.Sh SYNOPSIS
.Fd "#define _WITH_DPRINTF"
.In stdio.h		.In stdio.h
.Ft int		.Ft int
.Fn printf "const char * restrict format" ...		.Fn printf "const char * restrict format" ...
.Ft int		.Ft int
.Fn fprintf "FILE * restrict stream" "const char * restrict format" ...		.Fn fprintf "FILE * restrict stream" "const char * restrict format" ...
.Ft int		.Ft int
.Fn sprintf "char * restrict str" "const char * restrict format" ...		.Fn sprintf "char * restrict str" "const char * restrict format" ...
.Ft int		.Ft int
▲ Show 20 Lines • Show All 656 Lines • ▼ Show 20 Lines	if ((p = malloc(128)) == NULL)
return (NULL);		return (NULL);
va_start(ap, fmt);		va_start(ap, fmt);
(void) vsnprintf(p, 128, fmt, ap);		(void) vsnprintf(p, 128, fmt, ap);
va_end(ap);		va_end(ap);
return (p);		return (p);
}		}
.Ed		.Ed
.Sh COMPATIBILITY		.Sh COMPATIBILITY
Many application writers used the name
.Va dprintf
before the
.Fn dprintf
function was introduced in
.St -p1003.1 ,
so a prototype is not provided by default in order to avoid
compatibility problems.
Applications that wish to use the
.Fn dprintf
function described herein should either request a strict
.St -p1003.1-2008
environment by defining the macro
.Dv _POSIX_C_SOURCE
to the value 200809 or greater, or by defining the macro
.Dv _WITH_DPRINTF ,
prior to the inclusion of
.In stdio.h .
For compatibility with GNU libc, defining either
.Dv _BSD_SOURCE
or
.Dv _GNU_SOURCE
prior to the inclusion of
.In stdio.h
will also make
.Fn dprintf
available.
.Pp
The conversion formats		The conversion formats
.Cm \&%D , \&%O ,		.Cm \&%D , \&%O ,
and		and
.Cm \&%U		.Cm \&%U
are not standard and		are not standard and
are provided only for backward compatibility.		are provided only for backward compatibility.
The effect of padding the		The effect of padding the
.Cm %p		.Cm %p
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