Using LINUX commands in App Inventor. Extension

13.- df ::: du

df, information of device name, total blocks, total disk space, used disk space, available disk space and mount points on a file system.

df -h

du, check the information, size of files and directories.

du --help
du - h /mnt/sdcard/AppInventor/assets/logo1.png
du -h /mnt/sdcard/AppInventor/assets/
du -a /mnt/sdcard/AppInventor/assets/

14.- echo

We can use it to write text to a file.

echo “Scooby Doo, Where Are You!” > /mnt/sdcard/my_dog.txt
echo “I’m here!” >> /mnt/sdcard/my_dog.txt

15.- egrep ::: env ::: expand ::: expr ::: ext_logger ::: fallocate ::: false ::: fgrep ::: file ::

egrep, as grep -e (search expression).
env, enviroment variables.
expand, convert tabs into spaces in a file.
fallocate, allocated disk space for a file.
fgrep, as speed grep.
file, information of a file.

16.- find

Search files and directories.
find --help
find /mnt/sdcard/ -name *.txt (Search in all SdCard files *.txt)
find /mnt/sdcard/ -name *.png -o -name *.txt (List of files .png and .txt)
find /system/ -name *.apk (list where is apk files)
find /system/ -name *.apk > /mnt/sdcard/list_my_apk.txt

17.- free

Display the total, free and used amount of physical memory and swap space.

free -h

18.- getprop

Gets an Android system property, or lists them all.

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thank you, this is powerful…
is this an update to the existing extension from here?


Trying to push the limits! Snippets, Tutorials and Extensions from Pura Vida Apps by Taifun.


Great work @Juan_Antonio. Like @Taifun said. Really powerful.

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It is the same extension. This topic is only about its use.
Although in the next few days I will update it to be able to work with the asset files when the application is compiled, as @TIMAI2 proposed in a previous message.

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19.- grep

The grep is a filter that is used to search for lines matching a specified pattern and print the matching lines.

grep “seis” /mnt/sdcard/AppInventor/assets/numeros.txt
grep -r “seis” /mnt/sdcard/AppInventor/assets/numeros.txt
grep -v -e “six” /mnt/sdcard/AppInventor/assets/numeros.txt
grep -o -b “seven” /mnt/sdcard/AppInventor/assets/numeros.txt
grep -n “six” /mnt/sdcard/AppInventor/assets/numeros.txt

shell_grep.aia (11.5 KB)


20.- gunzip ::: gzip

gzip: zip and unzip
gunzip: unzip

gzip --help
gzip -k -c /mnt/sdcard/AppInventor/assets/numeros.txt > /mnt/sdcard/the_numeros.txt.gz

gzip -d -c /mnt/sdcard/the_numeros.txt.gz > /mnt/sdcard/los_numeros.txt

shell_gzip.aia (11.0 KB)


21.- head ::: tail

head -n 3 /mnt/sdcard/numeros.txt (shows the first three lines of the file)
tail -n 2 /mnt/sdcard/numeros.txt (shows the last two lines of the file)

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22.- ifconfig ::: ip ::: iw

ifconfig is used in LINUX to show/change network configuration,
but to modify the configuration you need to be root.

ifconfig wlan0 (shows IP)

ip net-tools which is used for performing several network administration tasks.

ip address show wlan0
ip n show
ip neigh show
ip -s neigh
ip -neighbour (to view MAC address of the devices connected to your system.)

iw (similar to ip)

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23.- kill ::: killall

kill command sends a signal to a process, if signal is 9 (default) kill a procces.

ps (get PID of process)
kill 19260 (kill MIT Companion)


killall (kill process by name)


24.- ln ::: logcat ::: logname

ln creates hard links by default, or symbolic links with -s ( –symbolic), it is a very important command in LINUX, but I cannot use it with AI2.

logcat -t 300 ( is a command -line tool that dumps a log of system messages)

logname (“name” user, example: u0_a173)

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25.- ls

list of files and directories.

ls -ali /mnt/sdcard/

-a (all, hidden .files)
-l (long format)
-i (show i-node number)

ls -ali /mnt/sdcard/ | grep 4096 (filter with grep lines with number 4096 (size))
ls -ali /mnt/sdcard/DCIM/
ls -ali /mnt/sdcard/DCIM/Camera > /mnt/sdcard/list_my_photos.txt

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26.- md5sum

Similar to cksum

md5sum --help
md5sum /mnt/sdcard/numeros.txt
74c22f5af060ac90932f7354261d887b numeros.txt

27.- mkdir

Create directory.

mkdir /mnt/sdcard/my_new_directory
mkdir -p /mnt/sdcard/directory/subdirectory/subsubdirectory

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28.- mount

mount, shows where the devices are mounted.

To mount devices you need to be root #

29.- mv

mv, move a file or directory, also used to rename a file or directory.

mv /mnt/sdcard/numeros.txt /mnt/sdcard/new_numeros.txt

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