$ ri --system -T IO | tail -10

Instance methods:
     <<, binmode, block_scanf, close, close_read, close_write, closed?,
     each, each_byte, each_line, eof, eof?, fcntl, fileno, flush,
     fsync, getc, gets, inspect, ioctl, isatty, lineno, lineno=, pid,
     pos, pos=, print, printf, putc, puts, read, read_nonblock,
     readbytes, readchar, readline, readlines, readpartial, reopen,
     rewind, scanf, seek, soak_up_spaces, stat, sync, sync=, sysread,
     sysseek, syswrite, tell, to_i, to_io, tty?, ungetc, write,
     write_nonblock


Notice that this listing contains two private methods block_scanf and
soak_up_spaces defined in lib/scanf.rb

-- 
Kent
---
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