Ruby latest stable (v2_5_5) - 0 notes - Class: IO
write(*args) public

Opens the file, optionally seeks to the given offset, writes string, then returns the length written. write ensures the file is closed before returning. If offset is not given in write mode, the file is truncated. Otherwise, it is not truncated.

IO.write("testfile", "0123456789", 20)  #=> 10
# File could contain:  "This is line one\nThi0123456789two\nThis is line three\nAnd so on...\n"
IO.write("testfile", "0123456789")      #=> 10
# File would now read: "0123456789"

If the last argument is a hash, it specifies options for the internal open(). It accepts the following keys:


string or encoding

Specifies the encoding of the read string. See Encoding.aliases for possible encodings.


string or integer

Specifies the mode argument for open(). It must start with “w”, “a”, or “r+”, otherwise it will cause an error. See for the list of possible modes.



Specifies the perm argument for open().



Specifies arguments for open() as an array. This key can not be used in combination with other keys.

Show source
Register or log in to add new notes.