DOKK / manpages / debian 11 / inn / shrinkfile.1.en
SHRINKFILE(1) General Commands Manual SHRINKFILE(1)

shrinkfile - shrink a file on a line boundary

shrinkfile [ -n ] [ -m maxsize ] [ -s size ] [ -v ] file...

The shrinkfile program shrinks files to a given size if the size is larger than maxsize,
preserving the data at the end of the file. Truncation is performed on line boundaries, where a line is a series of bytes ending with a newline, \n. There is no line length restriction and files may contain any binary data.

Temporary files are created in the /var/spool/news/in.coming/tmp directory. The ``TMPDIR'' environment variable may be used to specify a different directory.

A newline will be added to any non-empty file that does not end with a newline. The maximum file size will not be exceeded by this addition.

By default, size is assume to be zero and files are truncated to zero bytes. By default, maxsize is the same as size. If maxsize is less than size, maxsize is reset to size. The ``-s'' flag may be used to change the truncation size. Because the program truncates only on line boundaries, the final size may be smaller then the specified truncation size. The size and maxsize parameter may end with a ``k'', ``m'', or ``g'', indicating kilobyte (1024), megabyte (1048576) or gigabyte (1073741824) lengths. Uppercase letters are also allowed. The maximum file size is 2147483647 bytes.
If the ``-v'' flag is used, then shrinkfile will print a status line if a file was shrunk.
If the ``-n'' flag is used, then shrinkfile will exit 0 if any file is larger than maxsize and exit 1 otherwise. No files will be altered.

Example usage:

shrinkfile -s 4m curds
shrinkfile -s 1g -v whey
shrinkfile -s 500k -m 4m -v curds whey
if shrinkfile -n -s 100m whey; then echo whey is way too big; fi

Written by Landon Curt Noll <chongo@toad.com> and Rich $alz <rsalz@uunet.uu.net> for InterNetNews.