Linux Commands on Android

[christim]

I thought I'd start a thread on what some of the commands mean people are typing when rooted and see if there was any interest in this. I searched but did not find a similar thread but if there is let me know. I'll also include some other commands you can try out that you may not have used, especially if you are not familar with Linux or Unix.

These are typed in the terminal emulator, available for free from the market place as Android Terminal Emulator. Once downloaded it shows as Terminal Emulator in your app drawer.

Don't just randomly try commands. Some delete things so know what you are doing.

• chmod - give/take rights away from files. The numbers you see in the how-to's is a little complicated. It has to do with the rights you are assigning the file or folder. http://wiki.linuxquestions.org/wiki/Chmod for further reading.
• cat - look at, modify, or combine a file. You can also copy files with this command by "reading" it to another file instead of to the screen.
• cd - change from one directory to another
• cp - Copy a file from one location to another
• dd - copies exact locations to other locations. Can be an entire drive, a folder, etc. dd if=<file directory> of=<other directory>. uses an input file and an output file.
• exit - exits the shell you are in. When you type su you start up a shell.
• ls - lists all files with in a directory try ls - l too.
• mv - Move a file from one location to another. At the same time you can rename a file.
• su - Substitute User. We type this to switch to the root user. You need to type this command first to do a lot of the other commands.
• tar - creates taped archives. Compresses files like winzip, 7zip, winrar and others tar /? for details.
• rm - followed by a file name with delete the file
• sync - synchronizes any data on disk with data in memory. We type this before rebooting to ensure we've got all data written

Other commands of interest:

• df - how much free disk space. In linux you can add a switch "df -h" but the "-h" does nothing for me on Android.
• top - like task manager, it displays running processes. in Linux the q key quits. On Android I don't know how to make it quit other than closing the app.
• uptime - displays how long it has been since you last rebooted the system. Interestingly enough the "Menu Key > System > About Phone > Status > Up time" on my phone does not match "uptime" typed in the terminal emulator.

• busybox - a tool that combines many linux commands into a single compact file. Typing this displays all the commands at your disposal.
  • busybox df - a much easier to read display of free diskspace. This display shows how full (use%) each file system is.
    • Search the internet for what some of the other busybox commands do by just searching for something like "linux df".

If there are other good commands of interest post them here and I'll add them to this. Searching the internet will show you others as well.

You also can put a /? after the command so ls /? will display options. ls -l will do a long list vs the list short view

[thebowers]

Here is some more

ls - lists all files with in a directory
rm - followed by a file name with delete the file

there are many other commands and you can also make custom ones to shorten commands.

Edit: I think your first command is suppose to be chmod

[adrynalyne]

I thought I'd start a thread on what some of the commands mean people are typing when rooted and see if there was any interest in this. I searched but did not find a similar thread but if there is let me know. I'll also include some other commands you can try out that you may not have used, especially if you are not familar with Linux or Unix.

These are typed in the terminal emulator, available for free from the market place as Android Terminal Emulator. Once downloaded it shows as Terminal Emulator in your app drawer.

Don't just randomly try commands. Some delete things so know what you are doing.

• chmode - give/take rights away from files. The numbers you see in the how-to's is a little complicated. It has to do with the rights you are assigning the file or folder. http://wiki.linuxquestions.org/wiki/Chmod for further reading.
• cd - change from one directory to another
• cp - Copy a file from one location to another
• exit - exits the shell you are in. When you type su you start up a shell.
• mv - Move a file from one location to another. At the same time you can rename a file.
• su - Substitute User. We type this to switch to the root user. You need to type this command first to do a lot of the other commands.
• sync - synchronizes any data on disk with data in memory. We type this before rebooting to ensure we've got all data written

Other commands of interest:

• df - how much free disk space. In linux you can add a switch "df -h" but the "-h" does nothing for me on Android.
• top - like task manager, it displays running processes. in Linux the q key quits. On Android I don't know how to make it quit other than closing the app.
• uptime - displays how long it has been since you last rebooted the system. Interestingly enough the "Menu Key > System > About Phone > Status > Up time" on my phone does not match "uptime" typed in the terminal emulator.

• busybox - a tool that combines many linux commands into a single compact file. Typing this displays all the commands at your disposal.
  • busybox df - a much easier to read display of free diskspace. This display shows how full (use%) each file system is.
    • Search the internet for what some of the other busybox commands do by just searching for something like "linux df".

If there are other good commands of interest post them here and I'll add them to this. Searching the internet will show you others as well.

chmode should be chmod.

Many of these commands require busybox to not only be installed, but used in the command, unless you symlink the commands.

For example, cp would be used as busybox cp.

[adrynalyne]

cat can also be used to rename/move files.
tar is used as a command line compress/decompress utility.

[christim]

Here is some more

ls - lists all files with in a directory
rm - followed by a file name with delete the file

there are many other commands and you can also make custom ones to shorten commands.

Edit: I think your first command is suppose to be chmod

Right you are..I fixed "chmod", thanks. I was a little worried posting the rm command but if you have a backup you are all set. There's some recursive stuff that I won't be posting though

I'm used to the up-arrow at a command prompt scrolling through your history of commands. I don't know if that's terminal emulator not passing it through (d-pad?) or if this version of Linux just doesn't support it.

uname -a will display the version of Linux you are running.
for me it says:
2.6.29-Smoked_Glass #9
I'm running the SG4.5 rom at the moment.

[christim]

cat can also be used to rename/move files.
tar is used as a command line compress/decompress utility.

two good ones. cat is one used in instructions here too. dd is another one I just added as well, thanks!

cat is an interesting one to use for copying because it normally is used for viewing a file. By redirecting that viewing to another file, instead of defaulting to the screen we read the contents into another file...thus making a copy
cat file1.txt > file2.txt

[christim]

What does FU mean?

hey hey hey...this is a family rated site

Do you have an example of where you saw this in use? It is not a command I am familar with and when I try to FU it says "not found" so it isn't installed on my phone.

[h1br1d7heory]

I am trying to use chmod so I can write to /system/app.

I have tried the following with the following results:

chmod 755 /system/app
Unable to chmod /system/app: Read-only file system


The goal: I am trying to move some .apk files from my sdcard into that folder.

Can someone tell me what I am doing wrong?

[gustofusion]

I am trying to use chmod so I can write to /system/app.

I have tried the following with the following results:

chmod 755 /system/app
Unable to chmod /system/app: Read-only file system


The goal: I am trying to move some .apk files from my sdcard into that folder.

Can someone tell me what I am doing wrong?

run this fro a terminal then you can chmod

mount -o remount,rw -t ext3 /dev/block/mmcblk1p21 /system

[Se7enLC]

Good idea to put this all in one place!

The "-h" on df is to display in "human readable" format - ie, it splits sizes up into kb, mb, gb instead of just showing a really large number of kb. I believe some versions use this mode by default, so the -h may be unnecessary.

/? is for windows and does nothing for linux commands. In linux, the parameter is usually -h, or --help, and sometimes -?. Always a dash, though, never a slash.

Some other useful commands:
du - show disk usage of files. Add "-h" to get human readable. Especially useful when you add "-d1" to limit the directory depth to 1. If you run "du -h -d1", it will tell you how much space each directory occupies, including their contents summed.

rmdir - remove a directory. rm can't do it unless you remove recursively with -R
pm - android package manager. LOTS of useful things in here, type pm by itself for the help screen
ps - list processes. Useful to see what is running
kill - kill a process by PID
top - graphical display of processes, including cpu and memory use. hit 'q' to exit.
reboot - reboot
grep - search within a file for a text string. Also useful for parsing command output. 'ls | grep something' is a quick way to list files that contain the string "something" (although "ls *something*" would do it, too, but grep can do a lot more)
ping - see if an internet host is alive
ifconfig - get network interface configuration. Good for getting your own IP address.