File system

The Lua RTOS file system functions provides access to the supported file systems. Some functions, such as create a directory, are provided as an extension of the Lua os and module.

File access functions are provided through the standard Lua io module. This functions are not covered in this wiki.

The functions of this module are organized in the following categories:

• Format functions
• File and directory management functions

Format functions

os.format(filesystem)

Format a file system. Because all data is removed in the format process the function ask for a confirmation.

Arguments:

• file system: a string identifying the file system. Can be either spiffs or fat.

Returns: nothing or an exception.

/ > os.format("fat")
All data in fat will be deleted. Continue? [y/n]: y
Formatting...
Initializing FAT area: 4% completed

File and directory management functions

os.cat(filename)

Show (but not modify) the contents of a text file to the screen.

Arguments:

• filename: file path to show. Path can be absolute or relative to current working directory.

Returns: nothing or an error.

os.cd(path)

Change the current working directory.

Arguments:

• path: directory path. Path can be absolute or relative to current working directory.

Returns: nothing.

/> os.cd("/examples")
/examples >

os.dmseg()

Show (but not modify) the contents of the system log file one screen at a time. The content is paging through text one screenful at a time.

Note: os.dmseg() is not available in file systems that use NOR flash technology for store it's data, such as SPIFFS.

os.edit(file)

Edits a file.

Arguments:

• file: file path. Can be absolute or relative to current working directory.

Returns: nothing

/> os.edit("autorun.lua")

os.ls([path])

List the path contents.

Arguments:

• path: directory path. This argument it's optional, and if is not provided the contents of the current directory are listed. Path can be absolute or relative to current working directory.

Returns: nothing

/> os.ls("/")
d              -        tmp
d              -        www
d              -        conf
d              -        log
d              -        lib
f             27        test1.lua
f            956        autorun.lua
f           1871        lcd.lua

Directory contents is listed on the screen in columns (separated by tab):

• first column: entry type (d = directory / f = file)
• second column: entry size in bytes
• third column: entry name

os.mkdir(path)

Make a directory.

Arguments:

• directory path. Path can be absolute or relative to current working directory.

Returns: true if success

-- Make a new directory named test into the current working directory

os.mkdir("test")
true

os.more(filename)

Show (but not modify) the contents of a text file one screen at a time. The content is paging through text one screenful at a time.

Arguments:

• filename: file path to show. Path can be absolute or relative to current working directory.

Returns: nothing or an error.

os.pwd()

Get the current working directory.

Arguments: nothing

Returns: the current directory

/examples > os.pwd()
/examples

os.remove(path)

Remove a file or a directory.

Arguments:

• path: file or directory path to remove. Path can be absolute or relative to current working directory.

Returns: nothing or an error.

os.rename(old path, new path)

Rename a file or a directory.

Arguments:

• old path: file or directory path to rename. Path can be absolute or relative to current working directory.
• new path: file or directory new path. Path can be absolute or relative to current working directory.

Returns: nothing or an error.

os.cp(source path,destination path)

Copy a file.

Arguments:

• source path: file source path
• destination path: file destination path

Returns: nothing

-- Copy autorun.lua into autorun.old
os.cp("/autorun.lua","/autorun.old")