atof( ) returning garbage; already included stdlib.h

In a program, I am converting a string read from stdin to a float. However, atof() returns garbage(3.217777*10e-39), which I saw in the watch list when debugging.

Code:

char name[MAXNAME];
float a;
cout << "What is the name? (press 'b' to go back to the menu)\n";
fgets(name, sizeof name, stdin);
replaceTrailingNl(name);

if (strcmp(name, "b") == 0 || strcmp(name, "B") == 0) {
    menu();
    return;
}

// problematic part ... 
char *abuf = new(std::nothrow) char [MAXLINE];
do {
    cout << "What is the amt?\n";
    fgets(abuf, sizeof abuf, stdin);
    replaceTrailingNl(abuf);     //replaces trailing newline with \0

    convertDollarToSpace(abuf);  // initial '$' is replaced by space
} while (atof(abuf) == 0);
delete abuf;

I also tried using sscanf( ), but I also got garbage

Many answers on the Internet say to include <stdlib.h>. But I've already done so. Here is the top of the file, if that helps:

#include <iostream>
#include <cstdio>
#include <cstring>
#include <stdlib.h>
#include <cerrno>
#include <cctype>
#include "xaction.h" // a header containing a class