# fallocate > Reserve or deallocate disk space to files. > The utility allocates space without zeroing. > More information: . - Reserve a file taking up 700 MiB of disk space: `fallocate {{[-l|--length]}} {{700M}} {{path/to/file}}` - Shrink an already allocated file by 200 MiB: `fallocate {{[-c|--collapse-range]}} {{[-l|--length]}} {{200M}} {{path/to/file}}` - Shrink 20 MB of space after 100 MiB in a file: `fallocate {{[-c|--collapse-range]}} {{[-o|--offset]}} {{100M}} {{[-l|--length]}} {{20M}} {{path/to/file}}`