To create any file of given size in linux we can use dd command
Task is to create a file of size 10M
dd if=/dev/zero of=aa.txtt bs=1024 count=10240 10240+0 records in 10240+0 records out 10485760 bytes (10 MB) copied, 0.218581 seconds, 48.0 MB/s $ ls -hl output.dat -rw-r--r-- 1 raju raju 10M 2008-02-09 16:21 aa.txt The above dd command creates a zero-filled file named aa.txt consisting of a count of 10240 blocks, each of block size 1024. or you can use the below command which is more clear
$ dd if=/dev/zero of=aa.txt bs=1M count=10