NAME

readdir - directory input parser for gawk

SYNOPSIS

@load "readdir"

BEGIN { PROCINFO["readdir_override"] = any_value } # optional

DESCRIPTION

The readdir extension adds an input parser for directories.

When this extension is in use, instead of skipping directories named on
the command line (or with getline), they are read, with each entry
returned as a record.

The record consists of three fields separated by forward slash
characters. The first two are the inode number and the filename, and the
third field is a single letter indicating the type of the file: f for
file, d for directory, b for a block device, c for a character device, p
for a FIFO, l for a symbolic link, or s for a socket.

On systems where the directory entry contains the file type, the third
field is filled in from that information. On systems without the file
type information, the extension falls back to calling stat(2), in order
to provide the information. Thus the third field should never be u
(unknown).

Normally, when reading directories, you should set FS equal to "/".
However, you may instead chose to create PROCINFO["readdir_override"]
(with any value). If this element exists when the directory is opened,
then the extension automatically sets the fields in each record for you.

By default, if a directory cannot be opened (due to permission problems,
for example), gawk will exit. As with regular files, this situation can
be handled using a BEGINFILE rule that checks ERRNO and prints an error
or otherwise handles the problem.

EXAMPLE

    @load "readdir"
    ...
    BEGIN { FS = "/" }
    { print "file name is", $2 }

SEE ALSO

GAWK: Effective AWK Programming, and the man pages for the other
extensions shipped with gawk.

opendir(3), readdir(3), stat(2).

AUTHOR

Arnold Robbins, arnold@skeeve.com.

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