include "readdir.m";
readdir := load Readdir Readdir->PATH;

NAME, ATIME, MTIME, SIZE, NONE: con iota;
COMPACT:    con (1<<4);
DESCENDING: con (1<<5);
init:    fn(path: string, sortkey: int): (array of ref Sys->Dir, int);
readall: fn(fd: ref Sys->FD, sortkey: int): (array of ref Sys->Dir, int);
sortdir: fn(a: array of ref Sys->Dir, key: int): (array of ref Sys->Dir, int);

Init is most often used: it reads the contents of the directory path and sorts the resulting array according to sortkey.

The sorting criteria for the returned array are based on sortkey as follows:

NAME

Sort files alphabetically by name.

ATIME

Sort files by access time, most recently accessed first.

MTIME

Sort files by modification time, most recently modified first.

SIZE

Sort files by size, largest file first.

NONE

Files are left in directory order, unsorted.

If the value DESCENDING is or'd into any of the values above, except NONE, the order of sorting is reversed.

The sort used is stable, of particular importance in the presence of duplicate names in a union mount. If the value COMPACT is or'd into any of the values above, including NONE, only the first (outermost) entry with a given name will be returned from reading a union mount, if names are duplicated in the union.

Readall reads file descriptor fd which must be open on a directory, and returns the contents after applying sortkey as described above for init.

Sortdir sorts the array a according to the given key, as defined earlier, except that the COMPACT option has no effect.