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74

( sleep 300 ; echo "80" > /sys/class/leds/blue/brightness ) & That way your script continues, or you restore control immediately, while a new background task of the script starts, with two commands: sleep, and echo. The common error is trying to give either sleep or echo or both the & which will not work as intended. Launching a series of ...


31

Yum maintains a cache of the RPMs it downloads here: /var/cache/yum/<you architecture>/<OS version>/ For example my box is Fedora 14, x86_64 architecture so I have the following: $ ls /var/cache/yum/x86_64/14/ adobe-linux-i386 lamolabs rpmfusion-nonfree adobe-linux-x86_64 lamolabs-noarch ...


25

First, why there are separate /lib and /lib64: The Filesystem Hierarchy Standard mentions that separate /lib and /lib64 exist because: 10.1. There may be one or more variants of the /lib directory on systems which support more than one binary format requiring separate libraries. (...) This is commonly used for 64-bit or 32-bit support on systems ...


22

The reason is that the lib/lib64 directories can contain files which happen to have the same name because those are libraries shared with diverse programs. Putting them in separate directories solves the conflict. There's (usually...) no good reason for distributing same-named executables on the same system which are 32/64-bit, but since there can be a ...


22

Python is not mandatory for Linux, and there are plenty of small "embedded" Linux systems that don't have it. However, many distributions require it. So RHEL may have a dependency on Python because some of their management tools and scripts have been written in it. On those systems python is a requirement.


21

sudo is a a normal application with the suid bit. This means in order to use sudo it has to be installed on the system. Not all Linux systems have sudo installed per default like for example Debian. Most Android systems are targeted for end users who don't need to know the internals of Android (i.e. each Android applications runs under it's own user), so ...


19

boot.img is a small(ish) file that contain two main parts. * kernel(important for android) * ramdisk( a core set of instruction & binaries) Unpack boot.img: It contains the following steps: Download the tool using wget https://storage.googleapis.com/google-code-archive-downloads/v2/code.google.com/android-serialport-api/...


18

UPDATE: There are several, better alternatives to Airdroid now. However, it seems most Linux distros are now working with MTP fairly well. I know in my experience, Mint (Ubuntu based) works out of the box, as does Manjaro (Arch based). If it doesn't work out of the box or natively, then be sure to search your package manager for an MTP solution. Newer ...


18

The ext4 feature (400) is the new metadata_csum feature. If this feature is enabled and old tools are used to mount the filesystem they will only be able to mount read-only. https://ext4.wiki.kernel.org/index.php/Ext4_Metadata_Checksums To create a ext4 filesystem without this feature: sudo mke2fs /dev/sdb1 -O ^metadata_csum Or turn it off on an already ...


18

Python isn’t necessary, and it’s easy to prove: a basic Debian installation can get on the network etc. but doesn’t have Python. Python is an interpreter like any other. It can be required in some distributions, if their core tools (package managers etc.) are written in Python; other interpreters are required without anyone making a fuss about it (Perl for ...


14

use the at command echo "echo \"80\" > /sys/class/leds/blue/brightness" | at now + 5 min that will run in the background


13

The rpm files themselves are downloaded and then installed. Once these files are installed, they are tracked by the rpm database. To see where the files for a particular rpm were installed, you can run rpm -ql. E.g. [z@localhost ~]# rpm -ql bash |head /bin/bash /bin/sh /etc/skel/.bash_logout /etc/skel/.bash_profile /etc/skel/.bashrc /usr/bin/bashbug-64 /...


13

Linux Mint 17.1 Cinnamon 64-bit or a recent Ubuntu/Debian distribution. sudo apt-get update sudo apt-get install mtp-tools Unplug the USB cable and reconnect your Android device. The Android device should now be recognised as expected. If you are still having problems, please try the following. Check if you have other MTP software installed, run the ...


12

You can use ap-hotspot from the webupd8 repository to create an infrastracture AP instead of adhoc. I am using this on Ubuntu Precise (12.04), but it is available for Saucy, Raring and Quantal as well. $ sudo su - # add-apt-repository ppa:nilarimogard/webupd8 # aptitude update # aptitude install ap-hotspot # ap-hotspot configure # ap-hotspot start


12

Huge vim user myself, I faced the same question when moving in to Android Development a few years back. Originally I used Eclipse while Android Studio was still in development. Once Android Studio hit full release, the switch from Eclipse to Android Studio was another pain, but now Android Studio feels "good" to use. All I can say is download Android ...


11

Android runs MirBSD Korn shell mksh by default which is mostly a superset of sh. That has some limitations compared to bash scripts, for example one can't use arrays. Furthermore core utils are android specific toolbox or toybox applets, usage often is slightly different and sometimes limited (for example tar) Customized android devices use busybox as ...


10

sudo is not universal. Just because it exists on the particular Linux distro you use, doesn't mean it's available on all OSes that also use the Linux kernel.


10

You could try using the free (gratis) ES File Explorer file manager on your Android phone. Among a lot of functionality, it has an FTP server. So, if you can network your phone and your computer, you can easily transfer files both ways from your computer. I do it all the time from Ubuntu and Fedora machines (via Thunar). The FTP server mode in this app is ...


10

First, you must be clear that Google's Android code and Linux kernel code are separate. Android itself is licensed under Apache License 2.0, which is permissive, and in Wikipedia's words: The Apache License is permissive in that it does not require a derivative work of the software, or modifications to the original, to be distributed using the same ...


10

Android and Linux are two different operating systems. You can't just take an executable from one and run it on the other. The first hurdle is the kernel. Android and Linux are based on the same kernel, but they have a few different features. In particular, Android provides binders, which only exist in the mainstream kernel (the one found in Linux ...


9

The phone has to be rooted to have the root user install sudo (or any other app). Otherwise it would be installed as the "standard" user and not have root access. As for the second question, once sudo is installed on the rooted phone, in my experience, the apps that need it simply request it and you get a popup prompt.


9

See the Termux FAQ: the best way to fix this is to install termux-exec by running pkg install termux-exec and restarting your Termux session. Your scripts will then work without needing any changes.


8

The code that generates this file is in the unix_seq_show() function in net/unix/af_unix.c in the kernel source. Looking at include/net/af_unix.h is also helpful, to see the data structures in use. The socket path is always the last column in the output, and the Android kernel source matches the stock kernel in this respect. So unless I'm mistaken, that ...


7

For Arch Linux try : $ sudo vboxreload And for Mac try : $ sudo /Library/StartupItems/VirtualBox/VirtualBox restart


7

On Android, like on many Linux-based systems, the kernel first mounts an initramfs on /. The initramfs is stored in RAM; it is loaded from a CPIO archive which is stored together with the kernel itself (or in some other place where the bootloader can find it). Most desktop Linux systems have a small initramfs which contains just enough programs and ...


7

I think it's here. /data/system/packages.list


7

The error "EXT4-fs : couldn't mount RDWR because of unsupported optional features (400)" is due to different versions between the partition formatter (mkfs.ext4) and the mounter. You have two options: a) Either you have to upgrade the mounter program using a newer distro inside the SD-card. b) or you have to backup the files, reformat the SD-card with the ...


6

You can use a wiki like Zim - a Desktop Wiki and save its files to a Dropbox folder. For Android you can use WikiMind note to work with the Zim Wiki. I'm sure there are other apps that can work with Zim's files since they're just text with wiki markup. EDIT #1 Other options for Android if the $3 price for WikiMind is too steep. WikiMind Lite ZimDroid (it'...


6

"Linux", strictly speaking, is an operating system kernel used by both Android and the unix-like operating system referred to colloquially as linux, and sometimes more formally as GNU/Linux which we know via distributions such as ubuntu and debian. Linux, the operating system kernel, is written in C and must be compiled to native machine code. I think ...


6

You touch on a critical point in your question: a typical Linux install IS rooting: you boot from a Live CD and overwrite the bootsector of the harddrive to load your own code. It's just that rooting a PC is less arduous than on a semi embedded device like a phone so that people tend to forget that installing a second OS with dual-boot is essentially ...


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