Linux File Commands

Question 1

Compare files

Answer 1

diff file1 file2

Question 2

Force delete of

Answer 2

rm -rf

Question 3

Overite/delete file

Answer 3

shred -f -u

Question 4

Matches ref_file timestamp

Answer 4

touch -r

Question 5

Set file timestap

Answer 5

touch -t YYYMMDDHHSS

Question 6

List connected drives

Answer 6

sudo fdisk -l

Question 7

Mount USB key

Answer 7

mount /dev/sda# /mnt/usbkey

Question 8

Compute md5 hash

Answer 8

md5sum -t file

Question 9

Generate md5 hash

Answer 9

echo -n “str” | md5sum

Question 10

SHA1 hash of file

Answer 10

sha1sum file

Question 11

Sort/show unique lines

Answer 11

sort -u

Question 12

Count lines w/ “str”

Answer 12

grep -c “str” file

Question 13

Create .tar from file

Answer 13

tar cf file.tar files

Question 14

Extract .tar

Answer 14

tar xf file.tar

Question 15

Create .tar.gz

Answer 15

tar czf file.tar.gz files

Question 16

Extract .tar.gz

Answer 16

tar xzf file.tar.gz

Question 17

Create .tar.bz2

Answer 17

tar cjf file.tar.bz2 files

Question 18

Extract .tar.bz2

Answer 18

tar xjf file.tar.bz2

Question 19

Compress/rename file

Answer 19

gzip file

Question 20

Decompress file.gz

Answer 20

gzip -d file.gz

Question 21

UPX packs orig.exe

Answer 21

upx -9 -o out.exe orig.exe

Question 22

Create zip

Answer 22

zip -r \Directory*

Question 23

Cut block 1K-3K from file

Answer 23

dd skip=1000 count=2000 bs=8 if=file of=file

Question 24

Split file into 9K chunks

Answer 24

split -b 9K \

Question 25

Win compatible txt file

Answer 25

awk ‘sub(“$”.”\r”)’ unix.txt > win.txt

Question 26

Find PDF files

Answer 26

find -i -name -type *.pdf

Question 27

Search for setuid files

Answer 27

find / -perm -4000 -o -perm -2000 -exec ls -ldb {} \;

Question 28

Convert to *nix format

Answer 28

dos2unix

Question 29

Determine file type/info

Answer 29

file

Question 30

Set/Unset immutable bit

Answer 30

chattr (+/-)i