truncate
shrink or extend the size of a file to the specified size
TLDR
Set a size of 10 GB to an existing file, or create a new file with the specified size
Extend the file size by 50 MiB, fill with holes (which reads as zero bytes)
Shrink the file by 2 GiB, by removing data from the end of file
Empty the file's content
Empty the file's content, but do not create the file if it does not exist
SYNOPSIS
truncate OPTION... FILE...
DESCRIPTION
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.
- -c, --no-create
-
do not create any files
- -o, --io-blocks
-
treat SIZE as number of IO blocks instead of bytes
- -r, --reference=RFILE
-
base size on RFILE
- -s, --size=SIZE
-
set or adjust the file size by SIZE bytes
- --help
-
display this help and exit
- --version
-
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.
REPORTING BUGS
GNU coreutils online help:
<https://www.gnu.org/software/coreutils/>
Report any translation bugs to
<https://translationproject.org/team/>
COPYRIGHT
Copyright © 2023 Free Software Foundation, Inc. License GPLv3+: GNU
GPL version 3 or later <https://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it. There
is NO WARRANTY, to the extent permitted by law.
SEE ALSO
dd(1), truncate(2), ftruncate(2) Full documentation <https://www.gnu.org/software/coreutils/truncate> or available locally via: info '(coreutils) truncate invocation'
AUTHOR
Written by Padraig Brady.