position the file pointer 5 bytes from the end of the file and change the character to an X : seek « File Directory « Ruby

1. Ruby
2. File Directory
3. seek

position the file pointer 5 bytes from the end of the file and change the character to an X

IO::SEEK_CUR      Seeks a certain number of bytes ahead of the current position.
IO::SEEK_END      Seeks to a position based on the end of the file. 
IO::SEEK_SET      Seeks to an absolute position in the file. Identical to pos=.


f = File.new("test.txt", "r+")
f.seek(-5, IO::SEEK_END)
f.putc "X"
f.close

 

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