Bourne Shell Command Line Examples

Android Tutorials - Herong's Tutorial Examples

∟Bourne Shell Command Line Examples

This section provides a quick introduction of the Bourne shell which is the default shell on the Android system, which is based on the Linux system, which is based on Unix system.

Below is an example of Bourne shell session on my Android emulator. Explanations are provided in "()" below the output of the command.

herong> adb shell
#
      (Starting a Bourne shell session on the Android emulator)

# set
set
ANDROID_ASSETS=/system/app
ANDROID_BOOTLOGO=1
ANDROID_DATA=/data
ANDROID_PROPERTY_WORKSPACE=8,0
ANDROID_ROOT=/system
ASEC_MOUNTPOINT=/mnt/asec
BOOTCLASSPATH=/system/framework/core.jar:/system/framework/core-ju...
ANDROID_STORAGE=/storage
IFS='
'
LD_LIBRARY_PATH=/vendor/lib:/system/lib
LOOP_MOUNTPOINT=/mnt/obb
OPTIND=1
PATH=/sbin:/vendor/bin:/system/sbin:/system/bin:/system/xbin
PS1='# '
PS2='> '
PS4='+ '
      (Displays the values of all shell variables)

# PS1=\$
PS1=\$
$
      (Sets the shell prompt to the dollar sign $)

$ cd /sdcard/Download
cd /sdcard/Download
      (Changes directory to /sdcard/Download)

$ D=`pwd`
D=`pwd`
      (Sets the current working directory to variable D)

$ echo $D
echo $D
/sdcard/Download
      (Displays the value in variable D)

$ date
date
Sub Mar  1 22:20:19 GMT 2015
      (Displays the date)

$ cat > myself
cat > myself
I am trying to learn Android systems
I am trying to learn Android systems
^D
      (Creates a file and lets you to enter some text)

$ ls -l
ls -l
----rwxr-x system   sdcard_rw       36 2015-03-01 22:24 myself
      (Lists the contents of the current directory in long format)

$ cat myself
cat myself
I am trying to learn Android systems
      (Displays the contents of "myself" on the screen)

$ mkdir test
mkdir test
      (Makes a new directory)

$ touch test/myfile
touch test/myfile
      (Touches a file - Creates a new empty file)

$ rm test/myfile
rm test/myfile
      (Removes a file)

$ rmdir test
rmdir test
      (Removes a directory)