NAME

atof - convert a string to a float

atof - convert a string to a double

SYNOPSIS

Header File

#include <stdlib.h>

Prototype

float atof(string s);

#include <stdlib.h>

double atof(const char *nptr);

DESCRIPTION

This function converts a (positive or negative) floating-point value from a string (e.g., "50.0") to a float (e.g., 50.0).

The atof() function converts the initial portion of the string pointed to by nptr to double. The behavior is the same as

strtod(nptr, NULL);

except that atof() does not detect errors.

RETURN VALUE

This function returns its input, s, as a float.

The converted value.

EXAMPLE

#include <stdio.h>
#include <stdlib.h>

int main(void)
{
    printf("This is CS%.0f\n", atof("50.0"));
}

ATTRIBUTES

For an explanation of the terms used in this section, see attributes(7).

Interface Attribute Value
atof() Thread safety MT-Safe locale

CONFORMING TO

POSIX.1-2001, POSIX.1-2008, C89, C99, SVr4, 4.3BSD.

SEE ALSO

atoi(3), atol(3), strfromd(3), strtod(3), strtol(3), strtoul(3)

COLOPHON

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