teknoraver / alphanumsort

Alphanumeric sorting routine

alphanumsort

alphanumsort is a simple C/C++ function which compares strings that can have both and alphabetic and a numeric part. Alphabetic sort makes the numbers ordering non natural, e.g.

$ ls -1 /dev/tty*
/dev/tty
/dev/tty0
/dev/tty1
/dev/tty10
/dev/tty11
/dev/tty12
/dev/tty13
/dev/tty14
/dev/tty15
/dev/tty16
/dev/tty17
/dev/tty18
/dev/tty19
/dev/tty2
/dev/tty20
/dev/tty3
/dev/tty4
/dev/tty5
/dev/tty6
/dev/tty7
/dev/tty8
/dev/tty9

alphanumsort take cares of the numeric part and orders them by their numeric value:

$ ./test_c /dev/tty*
/dev/tty
/dev/tty0
/dev/tty1
/dev/tty2
/dev/tty3
/dev/tty4
/dev/tty5
/dev/tty6
/dev/tty7
/dev/tty8
/dev/tty9
/dev/tty10
/dev/tty11
/dev/tty12
/dev/tty13
/dev/tty14
/dev/tty15
/dev/tty16
/dev/tty17
/dev/tty18
/dev/tty19
/dev/tty20

Usage

Just include the corresponding header, alphanumsort_c.h or alphanumsort_cpp.h file and use it.
In C do it like:

char *strings[];
qsort(strings, num_strings, sizeof(*strings), alphanumsort);

In C++:

std::vector<std::string> strings;
std::sort(strings.begin(), strings.end(), alphanumsort);