atof.3

UNIX版本6的源代码

.th ATOF III 4/30/73
.sh NAME
atof \*- convert ASCII to floating
.sh SYNOPSIS
.ft B
double atof(nptr)
.br
char *nptr;
.br
.ft R
.sh DESCRIPTION
.it Atof
converts a string to a floating
number.
.it Nptr
should point to a string containing the number;
the first unrecognized character ends the number.
.s3
The only numbers recognized are:  an optional minus
sign followed by a string of digits optionally containing
one decimal point, then followed optionally by the
letter \fBe\fR followed by a signed integer.
.sh DIAGNOSTICS
There are none; overflow results in a very large
number and garbage characters terminate the scan.
.sh BUGS
The
routine should accept initial \fB+\fR, initial blanks, and \fBE\fR for \fBe\fR.
Overflow should be signalled.