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/*
Copyright (c) 1990 Regents of the University of California.
All rights reserved.
*/
/*
FUNCTION
<<ecvt>>, <<ecvtf>>, <<fcvt>>, <<fcvtf>>---double or float to string
INDEX
ecvt
INDEX
ecvtf
INDEX
fcvt
INDEX
fcvtf
SYNOPSIS
#include <stdlib.h>
char *ecvt(double <[val]>, int <[chars]>, int *<[decpt]>, int *<[sgn]>);
char *ecvtf(float <[val]>, int <[chars]>, int *<[decpt]>, int *<[sgn]>);
char *fcvt(double <[val]>, int <[decimals]>,
int *<[decpt]>, int *<[sgn]>);
char *fcvtf(float <[val]>, int <[decimals]>,
int *<[decpt]>, int *<[sgn]>);
DESCRIPTION
<<ecvt>> and <<fcvt>> produce (null-terminated) strings of digits
representating the <<double>> number <[val]>.
<<ecvtf>> and <<fcvtf>> produce the corresponding character
representations of <<float>> numbers.
(The <<stdlib>> functions <<ecvtbuf>> and <<fcvtbuf>> are reentrant
versions of <<ecvt>> and <<fcvt>>.)
The only difference between <<ecvt>> and <<fcvt>> is the
interpretation of the second argument (<[chars]> or <[decimals]>).
For <<ecvt>>, the second argument <[chars]> specifies the total number
of characters to write (which is also the number of significant digits
in the formatted string, since these two functions write only digits).
For <<fcvt>>, the second argument <[decimals]> specifies the number of
characters to write after the decimal point; all digits for the integer
part of <[val]> are always included.
Since <<ecvt>> and <<fcvt>> write only digits in the output string,
they record the location of the decimal point in <<*<[decpt]>>>, and
the sign of the number in <<*<[sgn]>>>. After formatting a number,
<<*<[decpt]>>> contains the number of digits to the left of the
decimal point. <<*<[sgn]>>> contains <<0>> if the number is positive,
and <<1>> if it is negative.
RETURNS
All four functions return a pointer to the new string containing a
character representation of <[val]>.
PORTABILITY
None of these functions are ANSI C.
Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
<<lseek>>, <<read>>, <<sbrk>>, <<write>>.
NEWPAGE
FUNCTION
<<gcvt>>, <<gcvtf>>---format double or float as string
INDEX
gcvt
INDEX
gcvtf
SYNOPSIS
#include <stdlib.h>
char *gcvt(double <[val]>, int <[precision]>, char *<[buf]>);
char *gcvtf(float <[val]>, int <[precision]>, char *<[buf]>);
DESCRIPTION
<<gcvt>> writes a fully formatted number as a null-terminated
string in the buffer <<*<[buf]>>>. <<gcvtf>> produces corresponding
character representations of <<float>> numbers.
<<gcvt>> uses the same rules as the <<printf>> format
`<<%.<[precision]>g>>'---only negative values are signed (with
`<<->>'), and either exponential or ordinary decimal-fraction format
is chosen depending on the number of significant digits (specified by
<[precision]>).
RETURNS
The result is a pointer to the formatted representation of <[val]>
(the same as the argument <[buf]>).
PORTABILITY
Neither function is ANSI C.
Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
<<lseek>>, <<read>>, <<sbrk>>, <<write>>.
*/
#define _XOPEN_SOURCE
#define _XOPEN_SOURCE_EXTENDED
#include <_ansi.h>
#include <stdio.h>
#include <stdlib.h>
#include "local.h"
char * ecvtbuf (double, int, int*, int*, char *);
char * fcvtbuf (double, int, int*, int*, char *);
char *
fcvt (double d,
int ndigit,
int *decpt,
int *sign)
{
return fcvtbuf (d, ndigit, decpt, sign, NULL);
}
char *
fcvtf (float d,
int ndigit,
int *decpt,
int *sign)
{
return fcvt ((double) d, ndigit, decpt, sign);
}
char *
gcvt (double d,
int ndigit,
char *buf)
{
char *tbuf = buf;
if (d < 0) {
*buf = '-';
buf++;
ndigit--;
}
return (_gcvt (d, ndigit, buf, 'g', 0) ? tbuf : 0);
}
char *
gcvtf (float d,
int ndigit,
char *buf)
{
double asd = (double) d;
return gcvt (asd, ndigit, buf);
}
char *
ecvt (double d,
int ndigit,
int *decpt,
int *sign)
{
return ecvtbuf (d, ndigit, decpt, sign, NULL);
}
char *
ecvtf (float d,
int ndigit,
int *decpt,
int *sign)
{
return ecvt ((double) d, ndigit, decpt, sign);
}
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