TRUNCATE(1) User Commands TRUNCATE(1)

truncate - shrink or extend the size of a file to the specified size

truncate OPTION... FILE...

Shrink or extend the size of each FILE to the specified size

A FILE argument that does not exist is created.

If a FILE is larger than the specified size, the extra data is lost. If a FILE is shorter, it is extended and the sparse extended part (hole) reads as zero bytes.

Mandatory arguments to long options are mandatory for short options too.

do not create any files
treat SIZE as number of IO blocks instead of bytes
base size on RFILE
set or adjust the file size by SIZE bytes
display this help and exit
output version information and exit

The SIZE argument is an integer and optional unit (example: 10K is 10*1024). Units are K,M,G,T,P,E,Z,Y,R,Q (powers of 1024) or KB,MB,... (powers of 1000). Binary prefixes can be used, too: KiB=K, MiB=M, and so on.

SIZE may also be prefixed by one of the following modifying characters: '+' extend by, '-' reduce by, '<' at most, '>' at least, '/' round down to multiple of, '%' round up to multiple of.

Written by Padraig Brady.

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Copyright © 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.

dd(1), truncate(2), ftruncate(2)

Full documentation
or available locally via: info '(coreutils) truncate invocation'

April 2023 GNU coreutils 9.3