NAME

file - Fast IO operations using direct system calls

SYNOPSIS

use file;

# Slurp entire file
my $content = file::slurp('/path/to/file');

# Write to file
file::spew('/path/to/file', $content);

# Append to file
file::append('/path/to/file', "more data\n");

# Get all lines as array
my $lines = file::lines('/path/to/file');

# Process lines efficiently with callback
file::each_line('/path/to/file', sub {
    my $line = shift;
    print "Line: $line\n";
});

# Memory-mapped file access
my $mmap = file::mmap_open('/path/to/file');
my $data = $mmap->data;  # Zero-copy access
$mmap->close;

# Line iterator (memory efficient)
my $iter = file::lines_iter('/path/to/file');
while (!$iter->eof) {
    my $line = $iter->next;
    # process line
}
$iter->close;

# File stat operations
my $size   = file::size('/path/to/file');
my $mtime  = file::mtime('/path/to/file');
my $exists = file::exists('/path/to/file');

# Type checks
file::is_file('/path/to/file');
file::is_dir('/path/to/dir');
file::is_readable('/path/to/file');
file::is_writable('/path/to/file');

DESCRIPTION

Fast IO operations using direct system calls, bypassing PerlIO overhead. This module provides significantly faster file operations compared to Perl's built-in IO functions.

Performance

The module uses:

  • Direct read(2)/write(2) syscalls

  • Pre-allocated buffers based on file size

  • Memory-mapped file access for zero-copy reads

  • Efficient line iteration without loading entire file

FUNCTIONS

slurp

my $content = file::slurp($path);

Read entire file into a scalar. Returns undef on error. Pre-allocates the buffer based on file size for optimal performance.

slurp_raw

my $content = file::slurp_raw($path);

Same as slurp, explicit binary mode.

spew

my $ok = file::spew($path, $data);

Write data to file (creates or truncates). Returns true on success.

append

my $ok = file::append($path, $data);

Append data to file. Returns true on success.

lines

my $lines = file::lines($path);

Returns arrayref of all lines (without newlines).

each_line

file::each_line($path, sub {
    my $line = shift;
    # process line
});

Process each line with a callback. Memory efficient - doesn't load entire file into memory.

lines_iter

my $iter = file::lines_iter($path);
while (!$iter->eof) {
    my $line = $iter->next;
}
$iter->close;

Returns a line iterator object for memory-efficient line processing.

mmap_open

my $mmap = file::mmap_open($path);
my $mmap = file::mmap_open($path, 1);  # writable

Memory-map a file. Returns a file::mmap object.

file::mmap methods

data() - Returns the mapped content as a scalar (zero-copy)
sync() - Flush changes to disk (for writable maps)
close() - Unmap the file

size

my $bytes = file::size($path);

Returns file size in bytes, or -1 on error.

mtime

my $epoch = file::mtime($path);

Returns modification time as epoch seconds, or -1 on error.

exists

if (file::exists($path)) { ... }

Returns true if path exists.

is_file

if (file::is_file($path)) { ... }

Returns true if path is a regular file.

is_dir

if (file::is_dir($path)) { ... }

Returns true if path is a directory.

is_readable

if (file::is_readable($path)) { ... }

Returns true if path is readable.

is_writable

if (file::is_writable($path)) { ... }

Returns true if path is writable.

is_executable

if (file::is_executable($path)) { ... }

Returns true if path is executable.

if (file::is_link($path)) { ... }

Returns true if path is a symbolic link.

atime

my $epoch = file::atime($path);

Returns access time as epoch seconds, or -1 on error.

ctime

my $epoch = file::ctime($path);

Returns change time as epoch seconds, or -1 on error.

mode

my $mode = file::mode($path);

Returns file permission mode (e.g., 0644), or -1 on error.

my $ok = file::unlink($path);

Delete a file. Returns true on success.

copy

my $ok = file::copy($src, $dst);

Copy a file. Returns true on success. Preserves file permissions.

move

my $ok = file::move($src, $dst);

Move/rename a file. Returns true on success. Works across filesystems.

touch

my $ok = file::touch($path);

Create file or update modification time. Returns true on success.

chmod

my $ok = file::chmod($path, $mode);

Change file permissions. Returns true on success.

file::chmod('/path/to/file', 0755);

mkdir

my $ok = file::mkdir($path);
my $ok = file::mkdir($path, $mode);

Create a directory. Default mode is 0755. Returns true on success.

rmdir

my $ok = file::rmdir($path);

Remove an empty directory. Returns true on success.

readdir

my $entries = file::readdir($path);

Returns arrayref of directory entries (excluding . and ..).

atomic_spew

my $ok = file::atomic_spew($path, $data);

Write data atomically using a temp file + rename. Returns true on success. This is safe against partial writes and power failures.

basename

my $name = file::basename($path);

Returns the filename portion of a path.

file::basename('/path/to/file.txt')  # returns 'file.txt'

dirname

my $dir = file::dirname($path);

Returns the directory portion of a path.

file::dirname('/path/to/file.txt')  # returns '/path/to'

extname

my $ext = file::extname($path);

Returns the file extension including the dot.

file::extname('/path/to/file.txt')  # returns '.txt'

join

my $path = file::join(@parts);

Join path components with the appropriate separator.

file::join('path', 'to', 'file')  # returns 'path/to/file'
my $lines = file::head($path);
my $lines = file::head($path, $n);

Returns arrayref of first N lines (default 10).

tail

my $lines = file::tail($path);
my $lines = file::tail($path, $n);

Returns arrayref of last N lines (default 10).

CUSTOM OP IMPORT

For maximum performance, you can import function-style accessors that use custom ops instead of method calls:

use file qw(import);

my $content = file_slurp($path);     # custom op, fastest
file_spew($path, $data);
my $exists = file_exists($path);
my $size = file_size($path);
my $is_file = file_is_file($path);
my $is_dir = file_is_dir($path);
my $lines = file_lines($path);
file_unlink($path);
file_mkdir($path);
file_rmdir($path);
file_touch($path);
my $base = file_basename($path);
my $dir = file_dirname($path);
my $ext = file_extname($path);

Custom ops provide 2-6% additional speed over method calls.

LINE PROCESSING

Advanced line processing functions for filtering and transforming file content.

count_lines

my $count = file::count_lines($path);
my $count = file::count_lines($path, $predicate);

Count lines in a file. With a predicate, counts only matching lines.

my $total = file::count_lines($path);
my $non_blank = file::count_lines($path, 'is_not_blank');
my $long = file::count_lines($path, sub { length(shift) > 80 });

find_line

my $line = file::find_line($path, $predicate);

Find and return the first line matching a predicate. Returns undef if no match found.

my $comment = file::find_line($path, 'is_comment');
my $error = file::find_line($path, sub { /ERROR/ });

grep_lines

my $lines = file::grep_lines($path, $predicate);

Filter lines matching a predicate. Returns arrayref.

my $comments = file::grep_lines($path, 'is_comment');
my $non_blank = file::grep_lines($path, 'is_not_blank');
my $errors = file::grep_lines($path, sub { /ERROR|WARN/ });

map_lines

my $result = file::map_lines($path, $transform);

Transform each line. Returns arrayref of transformed values.

my $upper = file::map_lines($path, sub { uc(shift) });
my $lengths = file::map_lines($path, sub { length($_) });

LINE CALLBACKS

Register custom predicates for use with grep_lines, count_lines, etc.

register_line_callback

file::register_line_callback($name, $coderef);

Register a named predicate for line filtering.

file::register_line_callback('is_todo', sub { /TODO|FIXME/ });

# Now use it:
my $todos = file::grep_lines($path, 'is_todo');

list_line_callbacks

my $names = file::list_line_callbacks();

Returns arrayref of all registered callback names.

Built-in predicates: is_blank, is_not_blank, blank, not_blank, is_empty, is_not_empty, is_comment, is_not_comment.

AUTHOR

LNATION

LICENSE

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.