"r" | Read-only, starts at beginning of file (default mode). |
"r+" | Read-write, starts at beginning of file. |
"w" | Write-only, truncates existing file to zero length or creates a new file for writing. |
"w+" | Read-write, truncates existing file to zero length or creates a new file for reading and writing. |
"a" | Write-only, starts at end of file if file exists, otherwise creates a new file for writing. |
"a+" | Read-write, starts at end of file if file exists, otherwise creates a new file for reading and writing. |
"b" | Binary file mode. Suppresses EOL <-> CRLF conversion on Windows. And sets external encoding to ASCII-8BIT unless explicitly specified. (This flag may only appear in conjunction with the above flags. For example, File.new("test.txt", "rb") would open test.txt in read-only mode as a binary file.) |
"t" | Text file mode. (This flag may only appear in conjunction with the above flags. For example, File.new("test.txt", "wt") would open test.txt in write-only mode as a text file.) |