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    Length: 1882 (0x75a)
    Types: TextFile
    Names: »number.c«

└─⟦db229ac7e⟧ Bits:30007240 EUUGD20: SSBA 1.2 / AFW Benchmarks
    └─⟦this⟧ »EUUGD20/AFUU-ssba1.21/ssba1.21E/musbus/number.c« 
    └─⟦this⟧ »EUUGD20/AFUU-ssba1.21/ssba1.21F/musbus/number.c« 

TextFile

/* Copyright (c) 1982, 1985 Gary Perlman */
/* Copies can be made if not for material gain */
#include <ctype.h>

#ifndef lint
static char sccsfid[] = "@(#) number.c 5.2 (unix|stat) 9/1/85";
#endif

#define	IS_NOT      0            /* not a number */
#define	IS_INT      1            /* an integer */
#define	IS_REAL     2            /* a real number */

#define	EOS         '\0'

/*LINTLIBRARY*/

number (string)
char	*string;                 /* the string to be tested */
	{
	int 	answer = IS_INT;     /* start by assuming it is an integer */
	int 	before = 0;          /* anything before the decimal? */
	int 	after = 0;           /* anything after the decimal? */
	while (isspace (*string))    /* skip over blank space */
		string++;
	if (*string == EOS)          /* empty string not allowed */
		return (IS_NOT);
	if (*string == '+' || *string == '-') /* old atoi didn't allow '+' */
		{
		string++;
		if (!isdigit (*string) && *string != '.')
			return (IS_NOT);
		}
	if (isdigit (*string))       /* note that there was a digit before . */
		{
		before = 1;
		while (isdigit (*string))
			string++;
		}
	if (*string == '.')          /* found a decimal point, parse for real */
		{
		answer = IS_REAL;
		string++;
		if (isdigit (*string))   /* note that there was a digit after . */
			{
			after = 1;
			while (isdigit (*string))
				string++;
			}
		}
	if (!before && !after)       /* must be digit somewhere */
		return (IS_NOT);
	if (*string == 'E' || *string == 'e') /* exponent */
		{
		answer = IS_REAL;
		string++;
		if (*string == '+' || *string == '-') /* optional sign */
			string++;
		if (!isdigit (*string))  /* missing exponent */
			return (IS_NOT);
		while (isdigit (*string))
			string++;
		}
	while (isspace (*string))    /* skip optional spaces */
		string++;
	/* should now have exhausted the input string */
	return (*string == EOS ? answer : IS_NOT);
	}