coreutils: truncate invocation

1 
1 14.5 ‘truncate’: Shrink or extend the size of a file
1 ====================================================
1 
1 ‘truncate’ shrinks or extends the size of each FILE to the specified
1 size.  Synopsis:
1 
1      truncate OPTION... FILE...
1 
1    Any FILE that does not exist is created.
1 
1    If a FILE is larger than the specified size, the extra data is lost.
1 If a FILE is shorter, it is extended and the extended part (or hole)
1 reads as zero bytes.
1 
11    The program accepts the following options.  Also see ⇒Common
 options.
1 
1 ‘-c’
1 ‘--no-create’
1      Do not create files that do not exist.
1 
1 ‘-o’
1 ‘--io-blocks’
1      Treat SIZE as number of I/O blocks of the FILE rather than bytes.
1 
1 ‘-r RFILE’
1 ‘--reference=RFILE’
1      Base the size of each FILE on the size of RFILE.
1 
1 ‘-s SIZE’
1 ‘--size=SIZE’
1      Set or adjust the size of each FILE according to SIZE.  SIZE is in
1      bytes unless ‘--io-blocks’ is specified.  SIZE may be, or may be an
1      integer optionally followed by, one of the following multiplicative
1      suffixes:
1           ‘KB’ =>           1000 (KiloBytes)
1           ‘K’  =>           1024 (KibiBytes)
1           ‘MB’ =>      1000*1000 (MegaBytes)
1           ‘M’  =>      1024*1024 (MebiBytes)
1           ‘GB’ => 1000*1000*1000 (GigaBytes)
1           ‘G’  => 1024*1024*1024 (GibiBytes)
1      and so on for ‘T’, ‘P’, ‘E’, ‘Z’, and ‘Y’.
1 
1      SIZE may also be prefixed by one of the following to adjust the
1      size of each FILE based on its current size:
1           ‘+’  => extend by
1           ‘-’  => reduce by
1           ‘<’  => at most
1           ‘>’  => at least
1           ‘/’  => round down to multiple of
1           ‘%’  => round up to multiple of
1 
1    An exit status of zero indicates success, and a nonzero value
1 indicates failure.
1