@c Documentation of gnulib module 'c-strtod'. @c Copyright (C) 2008--2023 Free Software Foundation, Inc. @c Permission is granted to copy, distribute and/or modify this document @c under the terms of the GNU Free Documentation License, Version 1.3 or @c any later version published by the Free Software Foundation; with no @c Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A @c copy of the license is at . The @code{c-strtod} module contains a string to number (@samp{double}) conversion function operating on single-byte character strings, that operates as if the locale encoding was ASCII. (The "C" locale on many systems has the locale encoding "ASCII".) The function is: @smallexample extern double c_strtod (const char *string, char **endp); @end smallexample In particular, only a period @samp{.} is accepted as decimal point, even when the current locale's notion of decimal point is a comma @samp{,}, and no characters outside the basic character set are accepted. On platforms without @code{strtod_l}, this function is not safe for use in multi-threaded applications since it calls @code{setlocale}.