Develop Reference

Starting adb logs on internal storage without going into the shell

I am trying to start internal logs within my android devices without having to go directly into the adb shell. I have to script this process so I can run it from a program.
I am aware that you can take the following steps to start internal logs on an android device:
Open a cmd prompt
enter 'adb shell'
enter 'logcat -v time -f /sdcard/LogFile.txt&'
The above will start a logcat process within the actual device. I can now unplug my phone from the computer and move around then come back and collect the logs once my test is complete. It's crucial that I am able to start this process and be able to unplug my device with the logs still running.
To my knowledge running 'adb shell' in front of any command would run as if it were in the shell. Therefore by this logic I tried running:
Method 1:
'adb shell logcat -v time -f /sdcard/LogFile.txt&'
This command did properly start the log on the device which is great. However, once I unplug from my computer the logcat process stops.
Method 2:
'adb shell "logcat -v time -f /sdcard/LogFile.txt&" '
This didn't seem to do anything at all on the phone and I don't know why.
Method 3
I have tried the scripting method as well where I run a Batch file that contains only:
'adb shell < Commands.txt'
Where commands has the single line:
'logcat -v time -f /sdcard/LogFile.txt&'
This doesn't appear to do anything. It appears to send the command once the window comes up but doesn't actually perform the action.
Any help on this topic would be greatly appreciated. Thanks.

you can use this code in application class. so when app will launch this code will start executing. and it will create new log file according to current time.
Thread t = new Thread(new Runnable() {
public void run() {
while (collectLog == true) {
try {
Thread.sleep(1000 * 60 * 6);
StringBuilder log = null;
Date now = new Date();
String fileName = formatter.format(now);
File file = new File(dir, fileName + "_logcat2.txt");
try {
Process process = Runtime.getRuntime().exec("logcat -d");// d will dump logs
//Process process = Runtime.getRuntime().exec("logcat -c"); c will clear logs
// process = Runtime.getRuntime().exec("logcat -f " + file);
BufferedReader bufferedReader = new BufferedReader(
new InputStreamReader(process.getInputStream()));
log = new StringBuilder();
String line;
while ((line = bufferedReader.readLine()) != null) {
log.append(line);
log.append("\n");
}
} catch (IOException e) {
}
try {
//to write logcat in text file
FileOutputStream fOut = new FileOutputStream(file);
OutputStreamWriter osw = new OutputStreamWriter(fOut)
// Write the string to the file
osw.append(log.toString());
osw.flush();
osw.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
});
t.start();

su behaves differently on adb and on program

I have a custom device android 4.3. Problem occurs with some commands, one of an example:
su -c 'pm enable com.android.systemui'
When I run this command over adb it works. However when I run the code programatically using this library it just does not work, no error is shown as well.
Interesting observations:
Shell.SU.available() : false
Shell.SU.isSELinuxEnforcing() : false

Ok so device is rooted. Any reason why you are trying to do that command using that library?
What I am trying to say is why can't you just run the shell command yourself?
runRootCommand method:
static boolean runRootCommand(String command) {
boolean status = true;
DataOutputStream os = null;
try {
Process process = Runtime.getRuntime().exec("su");
os = new DataOutputStream(process.getOutputStream());
os.writeBytes(command + "\n");
os.writeBytes("exit\n");
os.flush();
process.waitFor();
} catch (IOException | InterruptedException e) {
Log.e(TAG, e.toString());
status = false;
} finally {
try {
if (os != null)
os.close();
} catch (IOException e) {
Log.e(TAG, e.toString());
status = false;
}
}
return status;
}
And then call that method like this:
boolean success = runRootCommand("pm enable com.android.systemui");
if(success) {
// command was successful
} else {
// command was NOT successful
}
This will run the command as "su" (superuser).
Hope this helps.

what is the best way to interface a shell script to an android application?

Currently I have shell script commands which I run on android using terminal emulator application. Need to prepare an application to call the shell scripts from my android application show the result of the shell script on my application. Can anybody suggest the best way to do it.

Used code from here
public void runShellCommand(String[] cmds) throws Exception {
Process p = Runtime.getRuntime().exec("su");
DataOutputStream os = new DataOutputStream(p.getOutputStream());
InputStream is = p.getInputStream();
for (String temp : cmds) {
os.writeBytes(temp+"\n");
int read= 0;
byte[] buff = new byte[4096];
// if cmd requires an output
// due to the blocking behaviour of read(...)
boolean cmdRequiresAnOutput = true;
if (cmdRequiresAnOutput) {
while( is.available() <= 0) {
try { Thread.sleep(200); } catch(Exception ex) {}
}
while( is.available() > 0) {
read = is.read(buff);
if ( read <= 0 ) break;
String str = new String(buff,0,read);
console.println("#> "+str);
}
}
}
os.writeBytes("exit\n");
os.flush();
}
Sleep is required for commands that use long time.

How can check android Device is Rooted Device? [duplicate]

This question already has answers here:
Determine if running on a rooted device
(28 answers)
Closed 9 years ago.
How can i check if android device is rooted or not? I am using the following code:
Process proc = Runtime.getRuntime ().exec ("su");
and when I run it on a device I got following exception.
Causes by:Permission denied
But running on an emulator does not give any exception.
I am using another way to check. Entering adb shell in the commend line for emulator returns #, but for device writing adb shell gives the following error:
shell#android:/ $ su
su
/system/bin/sh: su: not found
127|shell#android:/ $
So how can I check if device is rooted or not.
Thanks in Advance.

I use this class:
private void CheckRoot()
{
Process p;
try {
// Preform su to get root privledges
p = Runtime.getRuntime().exec("su");
// Attempt to write a file to a root-only
DataOutputStream os = new DataOutputStream(p.getOutputStream());
os.writeBytes("echo \"Do I have root?\" >/data/LandeRootCheck.txt\n");
// Close the terminal
os.writeBytes("exit\n");
os.flush();
try {
p.waitFor();
if (p.exitValue() == 0) {
// TODO Code to run on success
this.IsRoot=true;
}
else {
// TODO Code to run on unsuccessful
this.IsRoot=false;
}
} catch (InterruptedException e) {
// TODO Code to run in interrupted exception
toastMessage("not root");
}
} catch (IOException e) {
// TODO Code to run in input/output exception
toastMessage("not root");
}
}

Run shell commands from android program

This question has been asked here before but the solutions provided are not working..I am trying to display the contents of /data/dalvik-cache folder. I know that to do this we need to become su. I even did that but still i am unable to execute a shell command..
package org.linuxconfidg.Example2;
import android.app.Activity;
import android.widget.*;
import android.os.Bundle;
import java.io.*;
public class Example2Activity extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
String lsreturn=myFunLs();
TextView tv=new TextView(this);
tv.setText("Hello Sindhu !! Try to get it \n"+lsreturn);
setContentView(tv);
}
public String myFunLs()
{
try {
// Executes the command.
Process process;
process = Runtime.getRuntime().exec("/system/bin/su");
process = Runtime.getRuntime().exec("/system/bin/ls /data/dalvik-cache > /data/local");
pr
BufferedReader reader = new BufferedReader(
new InputStreamReader(process.getInputStream()));
int read;
char[] buffer = new char[4096];
StringBuffer output = new StringBuffer();
while ((read = reader.read(buffer)) > 0) {
output.append(buffer, 0, read);
}
reader.close();
// Waits for the command to finish.
process.waitFor();
return output.toString();
} catch (IOException e) {
throw new RuntimeException(e);
} catch (InterruptedException e) {
throw new RuntimeException(e);
}
}
}
Can anyone please help me out in finding out how to run linux commands in android application. I am testing this app in my emulator which is defaultly rooted

You can't simply run 'su' on the emulator, there's no root access by default. You'll need to install the 'su' program as well as the SuperUser.apk, and you'll have to do this each time you start the emulator unless using snapshots.
More information and links to the files you need can be found here on SO as well as this blog post by Russell Davis

I think the problem comes from the fact that you are using TWO different process instances.
You have to be on the su process to carry on sending commands:
You can check the question "Read command output inside su process"
for an answer.
Then I tried & managed to make working code (I'm sure it works!)
public void runAsRoot(String[] cmds) throws Exception {
Process p = Runtime.getRuntime().exec("su");
DataOutputStream os = new DataOutputStream(p.getOutputStream());
InputStream is = p.getInputStream();
for (String tmpCmd : cmds) {
os.writeBytes(tmpCmd+"\n");
int readed = 0;
byte[] buff = new byte[4096];
// if cmd requires an output
// due to the blocking behaviour of read(...)
boolean cmdRequiresAnOutput = true;
if (cmdRequiresAnOutput) {
while( is.available() <= 0) {
try { Thread.sleep(200); } catch(Exception ex) {}
}
while( is.available() > 0) {
readed = is.read(buff);
if ( readed <= 0 ) break;
String seg = new String(buff,0,readed);
console.println("#> "+seg);
}
}
}
os.writeBytes("exit\n");
os.flush();
}

In the below example, I try to execute "/system/bin/screencap" to capture android screen.
via adb:
> adb shell
# /system/bin/screencap -p /sdcard/myscreenshot.png
via Android app:
sh = Runtime.getRuntime().exec("su", null,null);
OutputStream os = sh.getOutputStream();
os.write(("/system/bin/screencap -p " + path).getBytes("ASCII"));
os.flush();
os.close();
sh.waitFor();
Hope this helps.