Clear standard input buffer for C program in Linux
Hello friends! i am writing a code in which i take inputs (numbers) from user and count the total number of positive, negative and zeros entered. I need to clear my standard input buffer before scanf() command. My compiler is completely ignoring the fflush(stdin) command. its not even showing any error!. I am using Linux(ubunto) platform. Help!
Code:
#include<stdio.h>
int main()
{
int pos=0,neg=0,zeros=0;
float num;
char ans='y';
while(ans=='y')
{
printf("Enter a number : ");
scanf("%f",&num);
if(num>0)
{
pos++;
}
else if(num<0)
{
neg++;
}
else
{
zeros++;
}
printf("Wanna enter another number ? (y/n)\n");
fflush(stdin);
scanf("%c",&ans);
if(ans=='n')
{
printf("positive number : %d \n Negative numbers : %d \n Zeros : %d",pos,neg,zeros);
}
}
return 0;
}
Last edited by Abhishek_kumar; 08-08-2014 at 02:27 PM..
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LEARN ABOUT OSF1
rpmatch
rpmatch(3) Library Functions Manual rpmatch(3)NAME
rpmatch - Determines whether a response is affirmative or negative
LIBRARY
Standard C Library (libc.a)
SYNOPSIS
#include <stdlib.h>
int rpmatch( const char *response);
PARAMETERS
User input entered in response to a question that requires an affirmative or negative answer.
DESCRIPTION
The rpmatch() function determines whether the string value of the response parameter matches the affirmative or negative response expres-
sion as specified by the LC_MESSAGES category in the program's current locale. Both response expressions, defined in the locale, may be
extended regular expressions.
A possible value of the affirmative expression, yesexpr, for a English-language locale is "^([yY]|[yY][eE][sS])". This expression will
match any value of the response parameter that has consists of the letter Y (in uppercase or lowercase) or the letters YES (in any mixture
of uppercase and lowercase letters).
EXAMPLES
The following example requests a response from the user and uses the rpmatch() function to determine if the response is affirmative or neg-
ative.
#include <stdlib.h> #include <stdio.h> #include <locale.h> #include <string.h> #define SLENGTH 80
main() {
char str[SLENGTH], *eol;
int ans;
(void)setlocale(LC_ALL, "");
printf("Do you want to perform this operation: ");
fgets(str, SLENGTH, stdin);
if ((eol = strchr(str, '
')) != NULL)
*eol = '