1 /* Convert string to double, using the C locale.
3 Copyright (C) 2003-2004, 2009 Free Software Foundation, Inc.
5 This program is free software: you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 3 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>. */
18 /* Parse the initial portion of the string pointed to by NPTR as a floating-
19 point number (in decimal or hexadecimal notation), like in the C locale:
20 accepting only the ASCII digits '0'..'9', and only '.' as decimal point
21 character.
22 If ENDPTR is not NULL, set *ENDPTR to point to the first byte beyond the
23 parsed number or to NPTR if the string does not start with a parseable
24 number.
25 Return value:
26 - If successful, return the value as a double or 'long double',
27 respectively, and don't modify errno.
28 - In case of overflow, return ±HUGE_VAL or ±HUGE_VALL, respectively, and
29 set errno to ERANGE.
30 - In case of underflow, return a value very near to 0 and set errno to
31 ERANGE.
32 - If the string does not start with a number at all, return 0 (and recall
33 that if ENDPTR != NULL, *ENDPTR is set to NPTR), and maybe set errno to
34 EINVAL.
35 - In case of other error, return 0 and set errno, for example to ENOMEM. */
36 extern double c_strtod (char const *nptr, char **endptr);
37 extern long double c_strtold (char const *nptr, char **endptr);