READDIR(2)READDIR(2)NAMEreaddir - read directory and sort files
SYNOPSIS
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);
DESCRIPTION
Readdir provides functions to read and sort the contents of a direc‐
tory. Each function returns its result as a tuple that represents the
directory contents as an array of references to Sys->Dir values, one
per file (see sys-stat(2) for a description of Dir). The integer ele‐
ment of the tuple is the number of entries returned, or -1 if there was
an error reading the directory. Readdir differs from sys-dirread (2)
in returning the contents of the whole directory, not just a chunk of
it, and in allowing the result to be sorted.
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 ear‐
lier, except that the COMPACT option has no effect.
SOURCE
/appl/lib/readdir.b
SEE ALSOsys-dirread(2)READDIR(2)
