• FILE_READ: open the file for reading, starting at the beginning of the file.
• FILE_WRITE: open the file for reading and writing, starting at the end of the file.

Note: only one file can be open at a time.

SD.open(filepath, mode)

mode (optional): the mode in which to open the file, defaults to FILE_READ - byte. one of:

• FILE_READ: open the file for reading
• FILE_TRUNCATE: open the file for writing, deleting its current contents
• FILE_APPEND: open the file for writing, appending to the end of the file

SD.open(filepath)
SD.open(filepath, write)
SD.open(filepath, write, append)

filename: the name the file to open, which can include directories (delimited by forward slashes, /) - char *

Opens a file on the SD card. If the file is opened for writing, it will be created if it doesn't already exist (but the directory containing it must already exist).

write (optional): whether to open the file for writing; defaults to false (read-only) - boolean

append (optional): if opening the file for writing, whether to append to the end of the file (or overwrite its current contents); defaults to true (append) - boolean

• File: close()

• File: close()

SD

open()

Description

Opens a file on the SD card. If the file is opened for writing, it will be created if it doesn't already exist.

Note that only one file can be open at a time.

Syntax

SD.open(filename)
SD.open(filename, write)
SD.open(filename, write, append)

Parameters

filename: the name of the file to open, which can include directories (delimited by forward slashes: /) - char *

write (optional): whether or not to open the file for writing; defaults to false (read-only) - boolean

append (optional): whether or not to append to the end of the file (or overwrite its current contents); defaults to true (append) - boolean

Returns

a File object referring to the opened file; if the file couldn't be opened, this object will evaluate to false in a boolean context, i.e. you can test the return value with "if (f)".

See also

• File.close()