why du -sh is not correct ?

sysdljr · 02-07-2017, 07:31 AM

HI,
I am testing LZ4 compress command in shell script.
after compress finished, run du -sh view filesize , result more than true value, but run ls -l result is normal.

filepath=/home/test.lz4
filesize=$(ls -l $filepath | awk '{print $5}')
filesize=$(du -sh $filepath | awk '{print $1}'

TenTenths · 02-07-2017, 07:56 AM

These are NOT the same thing.

Go read the man page on du.

Hint: Go read up on --apparent-size

du gives the disk usage size based on the block size (if your file has even 1 byte in a block then the whole block is considered used).
ls gives the file size.

sysdljr · 02-09-2017, 06:39 AM

Thank you very much.