[Q] Get Android build number in app - Android Q&A, Help & Troubleshooting

Hi there,
I am writing an app and for one of the features I need the firmware build number.
I know I can get the firmware version(like 4.1.1) with android.os.build but I need the build number of a rom(like "Rom version 1.0") thats stored in build.prop. I know I can parse the whole build.prop file and extract the 1 string of information but is there another way to get is faster and that it doesnt require root to use?
Grtz,
Thirith

---

Solved it
I solved my own question
Here is how I did it(in case somebody wants to achieve the same thing):
Code:
TextView tv = (TextView)findViewById(R.id.text1);
String input = "getprop |awk -F : '/build.display.id/ { print $2 }'";
execCommandLine(input, tv);
void execCommandLine(String command, TextView tv)
{
Runtime runtime = Runtime.getRuntime();
Process proc = null;
OutputStreamWriter osw = null;
// Running the Script
try
{
proc = runtime.exec("su");
osw = new OutputStreamWriter(proc.getOutputStream());
osw.write(command);
osw.flush();
osw.close();
}
// If return error
catch (IOException ex)
{
// Log error
Log.e("execCommandLine()", "Command resulted in an IO Exception: " + command);
return;
}
// Try to close the process
finally
{
if (osw != null)
{
try
{
osw.close();
}
catch (IOException e){}
}
}
try
{
proc.waitFor();
}
catch (InterruptedException e){}
// Display on screen if error
if (proc.exitValue() != 0)
{
Log.e("execCommandLine()", "Command returned error: " + command + "\n Exit code: " + proc.exitValue());
AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
builder.setMessage(command + "\nWas not executed sucessfully!");
builder.setNeutralButton("OK", null);
AlertDialog dialog = builder.create();
dialog.setTitle("Script Error");
dialog.show();
}
BufferedReader reader = new BufferedReader(
new InputStreamReader(proc.getInputStream()));
int read;
char[] buffer = new char[4096];
StringBuffer output = new StringBuffer();
try {
while ((read = reader.read(buffer)) > 0) {
output.append(buffer, 0, read);
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
String exit = output.toString();
if(exit != null && exit.length() == 0) {
exit = "Command executed Successfully but no output was generated";
}
tv.setText(exit);
}

---

Hi, thanks for making your code public!
Just got an error when trying your code into my app.
Line
Code:
execCommandLine(input, tv);
runs into this error:
Multiple markers at this line
- input cannot be resolved to a type
- Return type for the method is missing
- Syntax error on token ",", delete this
token
Click to expand...
Click to collapse
How do I fix it?

---

Ok, did a mistake with integrating the code. My whole activity:
Code:
package de.yanniks.cm_updatechecker;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import de.yanniks.cm_updatechecker.R;
import android.app.Activity;
import android.app.AlertDialog;
import android.os.Bundle;
import android.util.Log;
import android.widget.TextView;
public class UpdateChecker extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.updatecheck);
TextView tv = (TextView)findViewById(R.id.installedversion);
String input = "getprop |awk -F : '/build.display.id/ { print $2 }'";
execCommandLine(input, tv);}
void execCommandLine(String command, TextView tv)
{
Runtime runtime = Runtime.getRuntime();
Process proc = null;
OutputStreamWriter osw = null;
// Running the Script
try
{
proc = runtime.exec("su");
osw = new OutputStreamWriter(proc.getOutputStream());
osw.write(command);
osw.flush();
osw.close();
}
// If return error
catch (IOException ex)
{
// Log error
Log.e("execCommandLine()", "Command resulted in an IO Exception: " + command);
return;
}
// Try to close the process
finally
{
if (osw != null)
{
try
{
osw.close();
}
catch (IOException e){}
}
}
try
{
proc.waitFor();
}
catch (InterruptedException e){}
// Display on screen if error
if (proc.exitValue() != 0)
{
Log.e("execCommandLine()", "Command returned error: " + command + "\n Exit code: " + proc.exitValue());
AlertDialog.Builder builder = new AlertDialog.Builder(UpdateChecker.this);
builder.setMessage(command + "\nWas not executed sucessfully!");
builder.setNeutralButton("OK", null);
AlertDialog dialog = builder.create();
dialog.setTitle("Script Error");
dialog.show();
}
BufferedReader reader = new BufferedReader(
new InputStreamReader(proc.getInputStream()));
int read;
char[] buffer = new char[4096];
StringBuffer output = new StringBuffer();
try {
while ((read = reader.read(buffer)) > 0) {
output.append(buffer, 0, read);
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
String exit = output.toString();
if(exit != null && exit.length() == 0) {
exit = "Command executed Successfully but no output was generated";
}
tv.setText(exit);
}
}

---

A better solution is to use my SystemProperties.get("build.display.id") directly instead of forking a native binary.
Code:
import java.io.FileDescriptor;
import java.io.FileInputStream;
import java.io.IOException;
import java.lang.reflect.Field;
import java.nio.ByteOrder;
import java.nio.MappedByteBuffer;
import java.nio.channels.FileChannel;
public class SystemProperties {
public static final int PROP_NAME_MAX= 32; // sic
public static final int PROP_VALUE_MAX= 92; // sic
public static final int PROP_AREA_MAGIC= 0x504f5250; // "PROP"
public static final int PROP_AREA_VERSION= 0x45434f76; // "vOCE" (API level 3..8 at least)
public static final String PROP_SERVICE_NAME= "property_service";
public static final String WORKSPACE= "ANDROID_PROPERTY_WORKSPACE";
// prop_area struct
public static final int PA_COUNT= 0;
public static final int PA_SERIAL= 4;
public static final int PA_MAGIC= 8;
public static final int PA_VERSION= 12;
public static final int PA_RESERVED= 16;
public static final int PA_TOC= 32;
public static final int PA_INFO_NAME= 0;
public static final int PA_INFO_SERIAL= PA_INFO_NAME+PROP_NAME_MAX;
public static final int PA_INFO_VALUE= PA_INFO_SERIAL+4;
private static MappedByteBuffer mMap= null;
private static boolean init() throws IllegalArgumentException,
SecurityException,
NoSuchFieldException,
IllegalAccessException,
IOException {
FileDescriptor fd;
MappedByteBuffer mbb= null;
String workspace= System.getenv(WORKSPACE);
if (workspace == null) {
throw new IllegalArgumentException(WORKSPACE + " not set");
}
String[] wsArray= workspace.split(",");
int osFd= 0;
int len= 0;
try {
osFd= new Integer(wsArray[0]);
} catch (NumberFormatException e) {
throw new IllegalArgumentException(e.getMessage());
}
try {
len= new Integer(wsArray[1]);
} catch (NumberFormatException e) {
throw new IllegalArgumentException(e.getMessage());
}
//Log.i(TAG, "Read fd " + Integer.toString(osFd) + " for " + len + " bytes.");
fd= new FileDescriptor();
Class<?> c= fd.getClass();
Field f= c.getDeclaredField("descriptor");
f.setAccessible(true);
f.setInt(fd, osFd);
FileInputStream in= new FileInputStream(fd);
FileChannel fc= in.getChannel();
mbb= fc.map(FileChannel.MapMode.READ_ONLY, 0, len);
mbb.order(ByteOrder.LITTLE_ENDIAN);
if (mbb.getInt(PA_MAGIC) != PROP_AREA_MAGIC) {
throw new IllegalArgumentException("Wrong kind of magic " + Integer.toString(mbb.getInt(PA_MAGIC), 16));
}
if (mbb.getInt(PA_VERSION) != PROP_AREA_VERSION) {
throw new IllegalArgumentException("Incorrect version " + Integer.toString(mbb.getInt(PA_VERSION), 16));
}
mMap= mbb;
return(true);
}
public static String get(String key) throws IllegalArgumentException,
SecurityException,
NoSuchFieldException,
IllegalAccessException,
IOException {
if (mMap == null) {
if (!init())
return(null);
}
int index= property_find(key);
//Log.i(TAG, "Found entry at " + Integer.toString(index));
if (index < 0)
return(null);
return(getString(index+PA_INFO_VALUE));
}
private static int property_find(String name) {
int count= mMap.getInt(PA_COUNT);
int tok= -1;
//Log.i(TAG, "Key " + name);
next: while(count-- > 0) {
tok++;
int entry= mMap.getInt(PA_TOC + tok*4);
//Log.i(TAG, "Entry " + tok + ": " + Integer.toString(entry, 16));
if ((entry >> 24) != name.length())
continue;
int index= (entry & 0xFFFFFF);
//Log.i(TAG, "Index " + index);
for (int i=0; i<name.length(); i++) {
//Log.i(TAG, "Cmp(" + entry + ":" + index + ":" + i + "): " + (char)(mbb.get(index+i)) + " -- " + name.charAt(i));
if ((char)(mMap.get(index+i)) != name.charAt(i)) {
continue next;
}
}
// found
return(index);
}
return(-1);
}
private static String getString(int index) {
byte b[]= new byte[PROP_VALUE_MAX];
int i= 0;
do {
b[i]= mMap.get(i+index);
} while (b[i++] != 0);
return(new String(b, 0, i-1));
}
}
Sorry 'bout the terrible indentation. Cut'n'paste isn't my code's best friend, obviously.