389 lines
12 KiB
C
389 lines
12 KiB
C
/*
|
|
* Copyright (c) 1990 The Regents of the University of California.
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms are permitted
|
|
* provided that the above copyright notice and this paragraph are
|
|
* duplicated in all such forms and that any documentation,
|
|
* advertising materials, and other materials related to such
|
|
* distribution and use acknowledge that the software was developed
|
|
* by the University of California, Berkeley. The name of the
|
|
* University may not be used to endorse or promote products derived
|
|
* from this software without specific prior written permission.
|
|
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
|
|
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
|
|
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
|
|
*/
|
|
|
|
/*
|
|
|
|
FUNCTION
|
|
<<printf>>, <<fprintf>>, <<asprintf>>, <<sprintf>>, <<snprintf>>---format output
|
|
INDEX
|
|
fprintf
|
|
INDEX
|
|
printf
|
|
INDEX
|
|
asprintf
|
|
INDEX
|
|
sprintf
|
|
INDEX
|
|
snprintf
|
|
|
|
ANSI_SYNOPSIS
|
|
#include <stdio.h>
|
|
|
|
int printf(const char *<[format]> [, <[arg]>, ...]);
|
|
int fprintf(FILE *<[fd]>, const char *<[format]> [, <[arg]>, ...]);
|
|
int sprintf(char *<[str]>, const char *<[format]> [, <[arg]>, ...]);
|
|
int asprintf(char **<[strp]>, const char *<[format]> [, <[arg]>, ...]);
|
|
int snprintf(char *<[str]>, size_t <[size]>, const char *<[format]> [, <[arg]>, ...]);
|
|
|
|
TRAD_SYNOPSIS
|
|
#include <stdio.h>
|
|
|
|
int printf(<[format]> [, <[arg]>, ...])
|
|
char *<[format]>;
|
|
|
|
int fprintf(<[fd]>, <[format]> [, <[arg]>, ...]);
|
|
FILE *<[fd]>;
|
|
char *<[format]>;
|
|
|
|
int asprintf(<[strp]>, <[format]> [, <[arg]>, ...]);
|
|
char **<[strp]>;
|
|
char *<[format]>;
|
|
|
|
int sprintf(<[str]>, <[format]> [, <[arg]>, ...]);
|
|
char *<[str]>;
|
|
char *<[format]>;
|
|
|
|
int snprintf(<[str]>, size_t <[size]>, <[format]> [, <[arg]>, ...]);
|
|
char *<[str]>;
|
|
size_t <[size]>;
|
|
char *<[format]>;
|
|
|
|
DESCRIPTION
|
|
<<printf>> accepts a series of arguments, applies to each a
|
|
format specifier from <<*<[format]>>>, and writes the
|
|
formatted data to <<stdout>>, terminated with a null character.
|
|
The behavior of <<printf>> is undefined if there are not enough
|
|
arguments for the format.
|
|
<<printf>> returns when it reaches the end of the format string.
|
|
If there are more arguments than the format requires, excess
|
|
arguments are ignored.
|
|
|
|
<<fprintf>>, <<asprintf>>, <<sprintf>> and <<snprintf>> are identical
|
|
to <<printf>>, other than the destination of the formatted output:
|
|
<<fprintf>> sends the output to a specified file <[fd]>, while
|
|
<<asprintf>> stores the output in a dynamically allocated buffer,
|
|
while <<sprintf>> stores the output in the specified char array
|
|
<[str]> and <<snprintf>> limits number of characters written to
|
|
<[str]> to at most <[size]> (including terminating <<0>>). For
|
|
<<sprintf>> and <<snprintf>>, the behavior is undefined if the
|
|
output <<*<[str]>>> overlaps with one of the arguments. For
|
|
<<asprintf>>, <[strp]> points to a pointer to char which is filled
|
|
in with the dynamically allocated buffer. <[format]> is a pointer
|
|
to a charater string containing two types of objects: ordinary
|
|
characters (other than <<%>>), which are copied unchanged to the
|
|
output, and conversion specifications, each of which is introduced
|
|
by <<%>>. (To include <<%>> in the output, use <<%%>> in the format
|
|
string.) A conversion specification has the following form:
|
|
|
|
. %[<[flags]>][<[width]>][.<[prec]>][<[size]>][<[type]>]
|
|
|
|
The fields of the conversion specification have the following meanings:
|
|
|
|
O+
|
|
o <[flags]>
|
|
|
|
an optional sequence of characters which control
|
|
output justification, numeric signs, decimal points,
|
|
trailing zeroes, and octal and hex prefixes.
|
|
The flag characters are minus (<<->>), plus (<<+>>),
|
|
space ( ), zero (<<0>>), and sharp (<<#>>). They can
|
|
appear in any combination.
|
|
|
|
o+
|
|
o -
|
|
The result of the conversion is left justified, and the right is
|
|
padded with blanks. If you do not use this flag, the result is right
|
|
justified, and padded on the left.
|
|
|
|
o +
|
|
The result of a signed conversion (as determined by <[type]>)
|
|
will always begin with a plus or minus sign. (If you do not use
|
|
this flag, positive values do not begin with a plus sign.)
|
|
|
|
o " " (space)
|
|
If the first character of a signed conversion specification
|
|
is not a sign, or if a signed conversion results in no
|
|
characters, the result will begin with a space. If the
|
|
space ( ) flag and the plus (<<+>>) flag both appear,
|
|
the space flag is ignored.
|
|
|
|
o 0
|
|
If the <[type]> character is <<d>>, <<i>>, <<o>>, <<u>>,
|
|
<<x>>, <<X>>, <<e>>, <<E>>, <<f>>, <<g>>, or <<G>>: leading zeroes,
|
|
are used to pad the field width (following any indication of sign or
|
|
base); no spaces are used for padding. If the zero (<<0>>) and
|
|
minus (<<->>) flags both appear, the zero (<<0>>) flag will
|
|
be ignored. For <<d>>, <<i>>, <<o>>, <<u>>, <<x>>, and <<X>>
|
|
conversions, if a precision <[prec]> is specified, the zero (<<0>>)
|
|
flag is ignored.
|
|
|
|
Note that <<0>> is interpreted as a flag, not as the beginning
|
|
of a field width.
|
|
|
|
o #
|
|
The result is to be converted to an alternative form, according
|
|
to the next character:
|
|
|
|
o+
|
|
o 0
|
|
increases precision to force the first digit
|
|
of the result to be a zero.
|
|
|
|
o x
|
|
a non-zero result will have a <<0x>> prefix.
|
|
|
|
o X
|
|
a non-zero result will have a <<0X>> prefix.
|
|
|
|
o e, E or f
|
|
The result will always contain a decimal point
|
|
even if no digits follow the point.
|
|
(Normally, a decimal point appears only if a
|
|
digit follows it.) Trailing zeroes are removed.
|
|
|
|
o g or G
|
|
same as <<e>> or <<E>>, but trailing zeroes
|
|
are not removed.
|
|
|
|
o all others
|
|
undefined.
|
|
|
|
o-
|
|
o-
|
|
|
|
o <[width]>
|
|
|
|
<[width]> is an optional minimum field width. You can either
|
|
specify it directly as a decimal integer, or indirectly by
|
|
using instead an asterisk (<<*>>), in which case an <<int>>
|
|
argument is used as the field width. Negative field widths
|
|
are not supported; if you attempt to specify a negative field
|
|
width, it is interpreted as a minus (<<->>) flag followed by a
|
|
positive field width.
|
|
|
|
o <[prec]>
|
|
|
|
an optional field; if present, it is introduced with `<<.>>'
|
|
(a period). This field gives the maximum number of
|
|
characters to print in a conversion; the minimum number of
|
|
digits of an integer to print, for conversions with <[type]>
|
|
<<d>>, <<i>>, <<o>>, <<u>>, <<x>>, and <<X>>; the maximum number of
|
|
significant digits, for the <<g>> and <<G>> conversions;
|
|
or the number of digits to print after the decimal
|
|
point, for <<e>>, <<E>>, and <<f>> conversions. You can specify
|
|
the precision either directly as a decimal integer or
|
|
indirectly by using an asterisk (<<*>>), in which case
|
|
an <<int>> argument is used as the precision. Supplying a negative
|
|
precision is equivalent to omitting the precision.
|
|
If only a period is specified the precision is zero.
|
|
If a precision appears with any other conversion <[type]>
|
|
than those listed here, the behavior is undefined.
|
|
|
|
o <[size]>
|
|
|
|
<<h>>, <<l>>, and <<L>> are optional size characters which
|
|
override the default way that <<printf>> interprets the
|
|
data type of the corresponding argument. <<h>> forces
|
|
the following <<d>>, <<i>>, <<o>>, <<u>>, <<x>> or <<X>> conversion
|
|
<[type]> to apply to a <<short>> or <<unsigned short>>. <<h>> also
|
|
forces a following <<n>> <[type]> to apply to
|
|
a pointer to a <<short>>. Similarily, an
|
|
<<l>> forces the following <<d>>, <<i>>, <<o>>, <<u>>,
|
|
<<x>> or <<X>> conversion <[type]> to apply to a <<long>> or
|
|
<<unsigned long>>. <<l>> also forces a following <<n>> <[type]> to
|
|
apply to a pointer to a <<long>>. <<l>> with <<c>>, <<s>> is
|
|
equivalent to <<C>>, <<S>> respectively. If an <<h>>
|
|
or an <<l>> appears with another conversion
|
|
specifier, the behavior is undefined. <<L>> forces a
|
|
following <<e>>, <<E>>, <<f>>, <<g>> or <<G>> conversion <[type]> to
|
|
apply to a <<long double>> argument. If <<L>> appears with
|
|
any other conversion <[type]>, the behavior is undefined.
|
|
|
|
o <[type]>
|
|
|
|
<[type]> specifies what kind of conversion <<printf>> performs.
|
|
Here is a table of these:
|
|
|
|
o+
|
|
o %
|
|
prints the percent character (<<%>>)
|
|
|
|
o c
|
|
prints <[arg]> as single character
|
|
|
|
o C
|
|
prints wchar_t <[arg]> as single multibyte character
|
|
|
|
o s
|
|
prints characters until precision is reached or a null terminator
|
|
is encountered; takes a string pointer
|
|
|
|
o S
|
|
converts wchar_t characters to multibyte output characters until
|
|
precision is reached or a null wchar_t terminator
|
|
is encountered; takes a wchar_t pointer
|
|
|
|
o d
|
|
prints a signed decimal integer; takes an <<int>> (same as <<i>>)
|
|
|
|
o i
|
|
prints a signed decimal integer; takes an <<int>> (same as <<d>>)
|
|
|
|
o o
|
|
prints a signed octal integer; takes an <<int>>
|
|
|
|
o u
|
|
prints an unsigned decimal integer; takes an <<int>>
|
|
|
|
o x
|
|
prints an unsigned hexadecimal integer (using <<abcdef>> as
|
|
digits beyond <<9>>); takes an <<int>>
|
|
|
|
o X
|
|
prints an unsigned hexadecimal integer (using <<ABCDEF>> as
|
|
digits beyond <<9>>); takes an <<int>>
|
|
|
|
o f
|
|
prints a signed value of the form <<[-]9999.9999>>; takes
|
|
a floating-point number
|
|
|
|
o e
|
|
prints a signed value of the form <<[-]9.9999e[+|-]999>>; takes a
|
|
floating-point number
|
|
|
|
o E
|
|
prints the same way as <<e>>, but using <<E>> to introduce the
|
|
exponent; takes a floating-point number
|
|
|
|
o g
|
|
prints a signed value in either <<f>> or <<e>> form, based on given
|
|
value and precision---trailing zeros and the decimal point are
|
|
printed only if necessary; takes a floating-point number
|
|
|
|
o G
|
|
prints the same way as <<g>>, but using <<E>> for the exponent if an
|
|
exponent is needed; takes a floating-point number
|
|
|
|
o n
|
|
stores (in the same object) a count of the characters written;
|
|
takes a pointer to <<int>>
|
|
|
|
o p
|
|
prints a pointer in an implementation-defined format.
|
|
This implementation treats the pointer as an
|
|
<<unsigned long>> (same as <<Lu>>).
|
|
o-
|
|
O-
|
|
|
|
|
|
RETURNS
|
|
<<sprintf>> and <<asprintf>> return the number of bytes in the output string,
|
|
save that the concluding <<NULL>> is not counted.
|
|
<<printf>> and <<fprintf>> return the number of characters transmitted.
|
|
If an error occurs, <<printf>> and <<fprintf>> return <<EOF>> and
|
|
<<asprintf>> returns -1. No error returns occur for <<sprintf>>.
|
|
|
|
PORTABILITY
|
|
The ANSI C standard specifies that implementations must
|
|
support at least formatted output of up to 509 characters.
|
|
|
|
Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
|
|
<<lseek>>, <<read>>, <<sbrk>>, <<write>>.
|
|
*/
|
|
|
|
#include <stdio.h>
|
|
#ifdef _HAVE_STDC
|
|
#include <stdarg.h>
|
|
#else
|
|
#include <varargs.h>
|
|
#endif
|
|
#include <limits.h>
|
|
#include <_ansi.h>
|
|
|
|
#ifndef _SMALL_PRINTF
|
|
#include "local.h"
|
|
#else
|
|
#ifdef INTEGER_ONLY
|
|
#define _vfprintf_r _vfiprintf_r
|
|
#endif
|
|
#endif
|
|
|
|
|
|
#ifndef _SMALL_PRINTF
|
|
int
|
|
#ifdef _HAVE_STDC
|
|
_DEFUN (_sprintf_r, (ptr, str, fmt), struct _reent *ptr _AND char *str _AND _CONST char *fmt _DOTS)
|
|
#else
|
|
_sprintf_r (ptr, str, fmt, va_alist)
|
|
struct _reent *ptr;
|
|
char *str;
|
|
_CONST char *fmt;
|
|
va_dcl
|
|
#endif
|
|
{
|
|
int ret;
|
|
va_list ap;
|
|
FILE f;
|
|
|
|
f._flags = __SWR | __SSTR;
|
|
f._bf._base = f._p = (unsigned char *) str;
|
|
f._bf._size = f._w = INT_MAX;
|
|
f._file = -1; /* No file. */
|
|
#ifdef _HAVE_STDC
|
|
va_start (ap, fmt);
|
|
#else
|
|
va_start (ap);
|
|
#endif
|
|
ret = _vfprintf_r (ptr, &f, fmt, ap);
|
|
va_end (ap);
|
|
*f._p = 0;
|
|
return (ret);
|
|
}
|
|
#endif
|
|
|
|
#ifndef _REENT_ONLY
|
|
int
|
|
#ifdef _HAVE_STDC
|
|
_DEFUN (sprintf, (str, fmt), char *str _AND _CONST char *fmt _DOTS)
|
|
#else
|
|
sprintf (str, fmt, va_alist)
|
|
char *str;
|
|
_CONST char *fmt;
|
|
va_dcl
|
|
#endif
|
|
{
|
|
int ret;
|
|
va_list ap;
|
|
FILE f;
|
|
|
|
f._flags = __SWR | __SSTR;
|
|
f._bf._base = f._p = (unsigned char *) str;
|
|
f._bf._size = f._w = INT_MAX;
|
|
f._file = -1; /* No file. */
|
|
#ifdef _HAVE_STDC
|
|
va_start (ap, fmt);
|
|
#else
|
|
va_start (ap);
|
|
#endif
|
|
ret = _vfprintf_r (_REENT, &f, fmt, ap);
|
|
va_end (ap);
|
|
*f._p = 0;
|
|
return (ret);
|
|
}
|
|
#endif
|
|
|
|
|