My program was not behaving correctly on one machine so I started to hunt for the bug, and I discovered that on that machine, snprintf uses a comma (,), not a . (dot) as 99% of
For library code, you may wish to use the POSIX 2008 uselocale
function instead of setlocale
. It is able to set a thread-specific locale, so that if your library code is called from a program that uses threads, it won't mess up the other threads' behavior (and/or crash the program, since setlocale
is not thread-safe).
For application code, you should simply avoid ever setting the LC_NUMERIC
locale category to anything but C/POSIX. The only categories you really need to set for most applications are LC_CTYPE
, LC_MESSAGES
, and possibly LC_COLLATE
.
You should be able to change your locale-setting using the setlocale
-function to make snprintf use a dot. Try setting it to "POSIX" or "C". (setlocale(LC_ALL, "POSIX")
.
versus ,
is set by the LC_NUMERIC
part of the locale. So make sure you set your program to use a locale that uses the .
(such as "POSIX"
).