787 lines
17 KiB
Groff
787 lines
17 KiB
Groff
.\" $NetBSD: printf.3,v 1.27 2002/10/01 17:24:06 wiz Exp $
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.\"
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.\" Copyright (c) 1990, 1991, 1993
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.\" The Regents of the University of California. All rights reserved.
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.\"
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.\" This code is derived from software contributed to Berkeley by
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.\" Chris Torek and the American National Standards Committee X3,
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.\" on Information Processing Systems.
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.\"
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.\" Redistribution and use in source and binary forms, with or without
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.\" modification, are permitted provided that the following conditions
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.\" are met:
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.\" 1. Redistributions of source code must retain the above copyright
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.\" notice, this list of conditions and the following disclaimer.
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.\" 2. Redistributions in binary form must reproduce the above copyright
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.\" notice, this list of conditions and the following disclaimer in the
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.\" documentation and/or other materials provided with the distribution.
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.\" 3. All advertising materials mentioning features or use of this software
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.\" must display the following acknowledgement:
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.\" This product includes software developed by the University of
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.\" California, Berkeley and its contributors.
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.\" 4. Neither the name of the University nor the names of its contributors
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.\" may be used to endorse or promote products derived from this software
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.\" without specific prior written permission.
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.\"
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.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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.\" SUCH DAMAGE.
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.\"
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.\" @(#)printf.3 8.1 (Berkeley) 6/4/93
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.\"
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.Dd December 2, 2001
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.Dt PRINTF 3
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.Os
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.Sh NAME
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.Nm printf ,
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.Nm fprintf ,
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.Nm sprintf ,
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.Nm snprintf ,
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.Nm asprintf ,
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.Nm vprintf ,
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.Nm vfprintf ,
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.Nm vsprintf ,
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.Nm vsnprintf ,
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.Nm vasprintf
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.Nd formatted output conversion
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.Sh LIBRARY
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.Lb libc
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.Sh SYNOPSIS
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.Fd #include \*[Lt]stdio.h\*[Gt]
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.Ft int
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.Fn printf "const char * restrict format" ...
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.Ft int
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|
.Fn fprintf "FILE * restrict stream" "const char * restrict format" ...
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.Ft int
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|
.Fn sprintf "char * restrict str" "const char * restrict format" ...
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.Ft int
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|
.Fn snprintf "char * restrict str" "size_t size" "const char * restrict format" ...
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.Ft int
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|
.Fn asprintf "char ** restrict ret" "const char * restrict format" ...
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.Fd #include \*[Lt]stdarg.h\*[Gt]
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.Ft int
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.Fn vprintf "const char * restrict format" "va_list ap"
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.Ft int
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.Fn vfprintf "FILE * restrict stream" "const char * restrict format" "va_list ap"
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.Ft int
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.Fn vsprintf "char * restrict str" "const char * restrict format" "va_list ap"
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.Ft int
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.Fn vsnprintf "char * restrict str" "size_t size" "const char * restrict format" "va_list ap"
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.Ft int
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.Fn vasprintf "char ** restrict ret" "const char * restrict format" "va_list ap"
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.Sh DESCRIPTION
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|
The
|
|
.Fn printf
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|
family of functions produces output according to a
|
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.Fa format
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|
as described below.
|
|
.Fn printf
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|
and
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|
.Fn vprintf
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|
write output to
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|
.Em stdout ,
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|
the standard output stream;
|
|
.Fn fprintf
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|
and
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|
.Fn vfprintf
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|
write output to the given output
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|
.Fa stream ;
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|
.Fn sprintf ,
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|
.Fn snprintf ,
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|
.Fn vsprintf ,
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|
and
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|
.Fn vsnprintf
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|
write to the character string
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|
.Fa str ;
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|
.Fn asprintf
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|
and
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|
.Fn vasprintf
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|
write to a dynamically allocated string that is stored in
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|
.Fa ret .
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|
.Pp
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|
These functions write the output under the control of a
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|
.Fa format
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|
string that specifies how subsequent arguments
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|
(or arguments accessed via the variable-length argument facilities of
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|
.Xr stdarg 3 )
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|
are converted for output.
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|
.Pp
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|
These functions return
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|
the number of characters printed
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|
(not including the trailing
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|
.Ql \e0
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|
used to end output to strings).
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|
.Pp
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|
.Fn asprintf
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|
and
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|
.Fn vasprintf
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|
return a pointer to a buffer sufficiently large to hold the
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|
string in the
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|
.Fa ret
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argument.
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|
This pointer should be passed to
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|
.Xr free 3
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|
to release the allocated storage when it is no longer needed.
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|
If sufficient space cannot be allocated, these functions
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|
will return -1 and set
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|
.Fa ret
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to be a NULL pointer.
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|
.Pp
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|
.Fn snprintf
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|
and
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|
.Fn vsnprintf
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|
will write at most
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|
.Fa size Ns \-1
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|
of the characters printed into the output string
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|
(the
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|
.Fa size Ns 'th
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|
character then gets the terminating
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|
.Ql \e0 ) ;
|
|
if the return value is greater than or equal to the
|
|
.Fa size
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|
argument, the string was too short
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|
and some of the printed characters were discarded.
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|
If
|
|
.Fa size
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|
is zero, nothing is written and
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|
.Fa str
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|
may be a NULL pointer.
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|
.Pp
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|
.Fn sprintf
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|
and
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|
.Fn vsprintf
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|
effectively assume an infinite
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|
.Fa size .
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|
.Pp
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|
The format string is composed of zero or more directives:
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|
ordinary
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|
.\" multibyte
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|
characters (not
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.Cm % ) ,
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|
which are copied unchanged to the output stream;
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and conversion specifications, each of which results
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in fetching zero or more subsequent arguments.
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|
Each conversion specification is introduced by
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the character
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|
.Cm % .
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|
The arguments must correspond properly (after type promotion)
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|
with the conversion specifier.
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|
After the
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|
.Cm % ,
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|
the following appear in sequence:
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|
.Bl -bullet
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|
.It
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|
Zero or more of the following flags:
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|
.Bl -hyphen
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.It
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A
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.Cm #
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|
character
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|
specifying that the value should be converted to an ``alternative form''.
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|
For
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|
.Cm c ,
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.Cm d ,
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.Cm i ,
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.Cm n ,
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|
.Cm p ,
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|
.Cm s ,
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|
and
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.Cm u ,
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conversions, this option has no effect.
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|
For
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.Cm o
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conversions, the precision of the number is increased to force the first
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character of the output string to a zero (except if a zero value is printed
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with an explicit precision of zero).
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|
For
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|
.Cm x
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|
and
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.Cm X
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|
conversions, a non-zero result has the string
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|
.Ql 0x
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(or
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|
.Ql 0X
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for
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.Cm X
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|
conversions) prepended to it.
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|
For
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|
.Cm e ,
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|
.Cm E ,
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|
.Cm f ,
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|
.Cm F ,
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|
.Cm g ,
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|
and
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|
.Cm G ,
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|
conversions, the result will always contain a decimal point, even if no
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digits follow it (normally, a decimal point appears in the results of
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|
those conversions only if a digit follows).
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|
For
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|
.Cm g
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|
and
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.Cm G
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|
conversions, trailing zeros are not removed from the result as they
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|
would otherwise be.
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.It
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|
A zero
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|
.Sq Cm \&0
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|
character specifying zero padding.
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|
For all conversions except
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|
.Cm n ,
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|
the converted value is padded on the left with zeros rather than blanks.
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|
If a precision is given with a numeric conversion
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|
.Pf ( Cm d ,
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|
.Cm i ,
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|
.Cm o ,
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|
.Cm u ,
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|
.Cm i ,
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|
.Cm x ,
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|
and
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|
.Cm X ) ,
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|
the
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|
.Sq Cm \&0
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|
flag is ignored.
|
|
.It
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|
A negative field width flag
|
|
.Sq Cm \-
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|
indicates the converted value is to be left adjusted on the field boundary.
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|
Except for
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|
.Cm n
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|
conversions, the converted value is padded on the right with blanks,
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|
rather than on the left with blanks or zeros.
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|
A
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|
.Sq Cm \-
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|
overrides a
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|
.Sq Cm \&0
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|
if both are given.
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|
.It
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|
A space, specifying that a blank should be left before a positive number
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|
produced by a signed conversion
|
|
.Pf ( Cm d ,
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|
.Cm e ,
|
|
.Cm E ,
|
|
.Cm f ,
|
|
.Cm F ,
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|
.Cm g ,
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|
.Cm G ,
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|
or
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|
.Cm i ) .
|
|
.It
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|
A
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|
.Sq Cm +
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|
character specifying that a sign always be placed before a
|
|
number produced by a signed conversion.
|
|
A
|
|
.Sq Cm +
|
|
overrides a space if both are used.
|
|
.El
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|
.It
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|
An optional decimal digit string specifying a minimum field width.
|
|
If the converted value has fewer characters than the field width, it will
|
|
be padded with spaces on the left (or right, if the left-adjustment
|
|
flag has been given) to fill out the field width.
|
|
.It
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|
An optional precision, in the form of a period
|
|
.Sq Cm \&.
|
|
followed by an optional digit string.
|
|
If the digit string is omitted, the precision is taken as zero.
|
|
This gives the minimum number of digits to appear for
|
|
.Cm d ,
|
|
.Cm i ,
|
|
.Cm o ,
|
|
.Cm u ,
|
|
.Cm x ,
|
|
and
|
|
.Cm X
|
|
conversions, the number of digits to appear after the decimal-point for
|
|
.Cm e ,
|
|
.Cm E ,
|
|
.Cm f ,
|
|
and
|
|
.Cm F
|
|
conversions, the maximum number of significant digits for
|
|
.Cm g
|
|
and
|
|
.Cm G
|
|
conversions, or the maximum number of characters to be printed from a
|
|
string for
|
|
.Cm s
|
|
conversions.
|
|
.It
|
|
The optional character
|
|
.Cm h ,
|
|
specifying that a following
|
|
.Cm d ,
|
|
.Cm i ,
|
|
.Cm o ,
|
|
.Cm u ,
|
|
.Cm x ,
|
|
or
|
|
.Cm X
|
|
conversion corresponds to a
|
|
.Em short int
|
|
or
|
|
.Em unsigned short int
|
|
argument, or that a following
|
|
.Cm n
|
|
conversion corresponds to a pointer to a
|
|
.Em short int
|
|
argument.
|
|
.It
|
|
The optional character
|
|
.Cm j ,
|
|
specifying that a following
|
|
.Cm d ,
|
|
.Cm i ,
|
|
.Cm o ,
|
|
.Cm u ,
|
|
.Cm x ,
|
|
or
|
|
.Cm X
|
|
conversion corresponds to an
|
|
.Em intmax_t
|
|
or
|
|
.Em uintmax_t
|
|
argument, or that a following
|
|
.Cm n
|
|
conversion corresponds to a pointer to a
|
|
.Em intmax_t
|
|
argument.
|
|
.It
|
|
The optional character
|
|
.Cm l
|
|
(ell) specifying that a following
|
|
.Cm d ,
|
|
.Cm i ,
|
|
.Cm o ,
|
|
.Cm u ,
|
|
.Cm x ,
|
|
or
|
|
.Cm X
|
|
conversion corresponds to a
|
|
.Em long int
|
|
or
|
|
.Em unsigned long int
|
|
argument, or that a following
|
|
.Cm n
|
|
conversion corresponds to a pointer to a
|
|
.Em long int
|
|
argument.
|
|
.It
|
|
The optional character
|
|
.Cm q ,
|
|
or alternatively two consecutive
|
|
.Cm l
|
|
(ell) characters,
|
|
specifying that a following
|
|
.Cm d ,
|
|
.Cm i ,
|
|
.Cm o ,
|
|
.Cm u ,
|
|
.Cm x ,
|
|
or
|
|
.Cm X
|
|
conversion corresponds to a
|
|
.Em quad_t
|
|
or
|
|
.Em u_quad_t
|
|
argument, or that a following
|
|
.Cm n
|
|
conversion corresponds to a pointer to a
|
|
.Em quad_t
|
|
argument.
|
|
.It
|
|
The optional character
|
|
.Cm t ,
|
|
specifying that a following
|
|
.Cm d ,
|
|
.Cm i ,
|
|
.Cm o ,
|
|
.Cm u ,
|
|
.Cm x ,
|
|
or
|
|
.Cm X
|
|
conversion corresponds to a
|
|
.Em ptrdiff_t
|
|
or
|
|
the corresponding unsigned integer type
|
|
argument, or that a following
|
|
.Cm n
|
|
conversion corresponds to a pointer to a
|
|
.Em ptrdiff_t
|
|
argument.
|
|
.It
|
|
The optional character
|
|
.Cm z ,
|
|
specifying that a following
|
|
.Cm d ,
|
|
.Cm i ,
|
|
.Cm o ,
|
|
.Cm u ,
|
|
.Cm x ,
|
|
or
|
|
.Cm X
|
|
conversion corresponds to a
|
|
.Em size_t
|
|
or
|
|
the corresponding signed integer type
|
|
argument, or that a following
|
|
.Cm n
|
|
conversion corresponds to a pointer to a
|
|
signed integer type corresponding to
|
|
.Em size_t
|
|
argument.
|
|
.It
|
|
The character
|
|
.Cm L
|
|
specifying that a following
|
|
.Cm e ,
|
|
.Cm E ,
|
|
.Cm f ,
|
|
.Cm F ,
|
|
.Cm g ,
|
|
or
|
|
.Cm G
|
|
conversion corresponds to a
|
|
.Em long double
|
|
argument.
|
|
.It
|
|
A character that specifies the type of conversion to be applied.
|
|
.El
|
|
.Pp
|
|
A field width or precision, or both, may be indicated by
|
|
an asterisk
|
|
.Ql *
|
|
instead of a digit string.
|
|
In this case, an
|
|
.Em int
|
|
argument supplies the field width or precision.
|
|
A negative field width is treated as a left adjustment flag followed by a
|
|
positive field width; a negative precision is treated as though it were
|
|
missing.
|
|
.Pp
|
|
The conversion specifiers and their meanings are:
|
|
.Bl -tag -width "diouxX"
|
|
.It Cm diouxX
|
|
The
|
|
.Em int
|
|
(or appropriate variant) argument is converted to signed decimal
|
|
.Pf ( Cm d
|
|
and
|
|
.Cm i ) ,
|
|
unsigned octal
|
|
.Pq Cm o ,
|
|
unsigned decimal
|
|
.Pq Cm u ,
|
|
or unsigned hexadecimal
|
|
.Pf ( Cm x
|
|
and
|
|
.Cm X )
|
|
notation.
|
|
The letters
|
|
.Cm abcdef
|
|
are used for
|
|
.Cm x
|
|
conversions; the letters
|
|
.Cm ABCDEF
|
|
are used for
|
|
.Cm X
|
|
conversions.
|
|
The precision, if any, gives the minimum number of digits that must
|
|
appear; if the converted value requires fewer digits, it is padded on
|
|
the left with zeros.
|
|
.It Cm DOU
|
|
The
|
|
.Em long int
|
|
argument is converted to signed decimal, unsigned octal, or unsigned
|
|
decimal, as if the format had been
|
|
.Cm ld ,
|
|
.Cm lo ,
|
|
or
|
|
.Cm lu
|
|
respectively.
|
|
These conversion characters are deprecated, and will eventually disappear.
|
|
.It Cm fF
|
|
The
|
|
.Em double
|
|
argument is rounded and converted to decimal notation in the style
|
|
.Sm off
|
|
.Pf [-]ddd Cm \&. No ddd ,
|
|
.Sm on
|
|
where the number of digits after the decimal-point character
|
|
is equal to the precision specification.
|
|
If the precision is missing, it is taken as 6; if the precision is
|
|
explicitly zero, no decimal-point character appears.
|
|
If a decimal point appears, at least one digit appears before it.
|
|
.Pp
|
|
If the double argument repesents an infinity it is converted
|
|
in the style
|
|
.Pf [-] Cm inf .
|
|
If the double argument represents a NaN it is converted
|
|
in the style
|
|
.Pf [-] Cm nan .
|
|
An
|
|
.Cm F
|
|
conversion produces
|
|
.Pf [-] Cm INF
|
|
and
|
|
.Pf [-] Cm NAN ,
|
|
respectively.
|
|
.It Cm eE
|
|
The
|
|
.Em double
|
|
argument is rounded and converted in the style
|
|
.Sm off
|
|
.Pf [\-]d Cm \&. No ddd Cm e No \\*(Pmdd
|
|
.Sm on
|
|
where there is one digit before the
|
|
decimal-point character
|
|
and the number of digits after it is equal to the precision;
|
|
if the precision is missing,
|
|
it is taken as 6; if the precision is
|
|
zero, no decimal-point character appears.
|
|
An
|
|
.Cm E
|
|
conversion uses the letter
|
|
.Cm E
|
|
(rather than
|
|
.Cm e )
|
|
to introduce the exponent.
|
|
The exponent always contains at least two digits; if the value is zero,
|
|
the exponent is 00.
|
|
.Pp
|
|
Double arguments representing infinities or NaNs are converted in the
|
|
same styles as in the
|
|
.Cm f
|
|
and
|
|
.Cm F
|
|
conversions.
|
|
.It Cm gG
|
|
The
|
|
.Em double
|
|
argument is converted in style
|
|
.Cm f
|
|
or
|
|
.Cm e
|
|
(or in style
|
|
.Cm F
|
|
or
|
|
.Cm E
|
|
for
|
|
.Cm G
|
|
conversions).
|
|
The precision specifies the number of significant digits.
|
|
If the precision is missing, 6 digits are given; if the precision is zero,
|
|
it is treated as 1.
|
|
Style
|
|
.Cm e
|
|
is used if the exponent from its conversion is less than -4 or greater than
|
|
or equal to the precision.
|
|
Trailing zeros are removed from the fractional part of the result; a
|
|
decimal point appears only if it is followed by at least one digit.
|
|
.Pp
|
|
Double arguments representing infinities or NaNs are converted in the
|
|
same styles as in the
|
|
.Cm f
|
|
and
|
|
.Cm F
|
|
conversions.
|
|
.It Cm c
|
|
The
|
|
.Em int
|
|
argument is converted to an
|
|
.Em unsigned char ,
|
|
and the resulting character is written.
|
|
.It Cm s
|
|
The
|
|
.Dq Em char *
|
|
argument is expected to be a pointer to an array of character type (pointer
|
|
to a string).
|
|
Characters from the array are written up to (but not including)
|
|
a terminating
|
|
.Dv NUL
|
|
character;
|
|
if a precision is specified, no more than the number specified are
|
|
written.
|
|
If a precision is given, no null character
|
|
need be present; if the precision is not specified, or is greater than
|
|
the size of the array, the array must contain a terminating
|
|
.Dv NUL
|
|
character.
|
|
.It Cm p
|
|
The
|
|
.Dq Em void *
|
|
pointer argument is printed in hexadecimal (as if by
|
|
.Ql %#x
|
|
or
|
|
.Ql %#lx ) .
|
|
.It Cm n
|
|
The number of characters written so far is stored into the
|
|
integer indicated by the
|
|
.Dq Em int *
|
|
(or variant) pointer argument.
|
|
No argument is converted.
|
|
.It Cm %
|
|
A
|
|
.Ql %
|
|
is written.
|
|
No argument is converted.
|
|
The complete conversion specification is
|
|
.Ql %% .
|
|
.El
|
|
.Pp
|
|
In no case does a non-existent or small field width cause truncation of
|
|
a field; if the result of a conversion is wider than the field width, the
|
|
field is expanded to contain the conversion result.
|
|
.Sh EXAMPLES
|
|
.br
|
|
To print a date and time in the form `Sunday, July 3, 10:02',
|
|
where
|
|
.Em weekday
|
|
and
|
|
.Em month
|
|
are pointers to strings:
|
|
.Bd -literal -offset indent
|
|
#include \*[Lt]stdio.h\*[Gt]
|
|
fprintf(stdout, "%s, %s %d, %.2d:%.2d\en",
|
|
weekday, month, day, hour, min);
|
|
.Ed
|
|
.Pp
|
|
To print \*(Pi
|
|
to five decimal places:
|
|
.Bd -literal -offset indent
|
|
#include \*[Lt]math.h\*[Gt]
|
|
#include \*[Lt]stdio.h\*[Gt]
|
|
fprintf(stdout, "pi = %.5f\en", 4 * atan(1.0));
|
|
.Ed
|
|
.Pp
|
|
To allocate a 128 byte string and print into it:
|
|
.Bd -literal -offset indent
|
|
#include \*[Lt]stdio.h\*[Gt]
|
|
#include \*[Lt]stdlib.h\*[Gt]
|
|
#include \*[Lt]stdarg.h\*[Gt]
|
|
char *newfmt(const char *fmt, ...)
|
|
{
|
|
char *p;
|
|
va_list ap;
|
|
if ((p = malloc(128)) == NULL)
|
|
return (NULL);
|
|
va_start(ap, fmt);
|
|
(void) vsnprintf(p, 128, fmt, ap);
|
|
va_end(ap);
|
|
return (p);
|
|
}
|
|
.Ed
|
|
.Sh SEE ALSO
|
|
.Xr printf 1 ,
|
|
.Xr scanf 3 ,
|
|
.Xr printf 9
|
|
.Sh STANDARDS
|
|
The
|
|
.Fn fprintf ,
|
|
.Fn printf ,
|
|
.Fn sprintf ,
|
|
.Fn vprintf ,
|
|
.Fn vfprintf ,
|
|
and
|
|
.Fn vsprintf
|
|
functions
|
|
conform to
|
|
.St -isoC90 .
|
|
The conversion format modifiers
|
|
.Cm %j ,
|
|
.Cm %t
|
|
and
|
|
.Cm %z
|
|
conform to
|
|
.St -isoC99 .
|
|
The
|
|
.Fn snprintf
|
|
and
|
|
.Fn vsnprintf
|
|
functions
|
|
conform to
|
|
.St -isoC99 .
|
|
.Sh HISTORY
|
|
The functions
|
|
.Fn snprintf
|
|
and
|
|
.Fn vsnprintf
|
|
first appeared in
|
|
.Bx 4.4 .
|
|
The functions
|
|
.Fn asprintf
|
|
and
|
|
.Fn vasprintf
|
|
are modeled on the ones that first appeared in the GNU C library.
|
|
.Sh CAVEATS
|
|
Because
|
|
.Fn sprintf
|
|
and
|
|
.Fn vsprintf
|
|
assume an infinitely long string, callers must be careful not to
|
|
overflow the actual space; this is often impossible to assure.
|
|
For safety, programmers should use the
|
|
.Fn snprintf
|
|
and
|
|
.Fn asprintf
|
|
family of interfaces instead.
|
|
Unfortunately, the
|
|
.Fn snprintf
|
|
interfaces are not available on older
|
|
systems and the
|
|
.Fn asprintf
|
|
interfaces are not yet portable.
|
|
.Pp
|
|
It is important never to pass a string with user-supplied data as a
|
|
format without using
|
|
.Ql %s .
|
|
An attacker can put format specifiers in the string to mangle your stack,
|
|
leading to a possible security hole.
|
|
This holds true even if you have built the string
|
|
.Dq by hand
|
|
using a function like
|
|
.Fn snprintf ,
|
|
as the resulting string may still contain user-supplied conversion specifiers
|
|
for later interpolation by
|
|
.Fn printf .
|
|
.Pp
|
|
Be sure to use the proper secure idiom:
|
|
.Bd -literal -offset indent
|
|
snprintf(buffer, sizeof(buffer), "%s", string);
|
|
.Ed
|
|
.Pp
|
|
There is no way for printf to know the size of each argument passed.
|
|
If you use positional arguments you must ensure that all parameters, up to the
|
|
last positionally specified parameter, are used in the format string.
|
|
This allows for the format string to be parsed for this information.
|
|
Failure to do this will mean your code is non-portable and liable to fail.
|
|
.Sh BUGS
|
|
The conversion formats
|
|
.Cm \&%D ,
|
|
.Cm \&%O ,
|
|
and
|
|
.Cm %U
|
|
are not standard and are provided only for backward compatibility.
|
|
The effect of padding the
|
|
.Cm %p
|
|
format with zeros (either by the
|
|
.Sq Cm 0
|
|
flag or by specifying a precision), and the benign effect (i.e. none)
|
|
of the
|
|
.Sq Cm #
|
|
flag on
|
|
.Cm %n
|
|
and
|
|
.Cm %p
|
|
conversions, as well as other nonsensical combinations such as
|
|
.Cm %Ld ,
|
|
are not standard; such combinations should be avoided.
|