Linux

The character device driver in Linux has a function Unsigned int (* poll) (struct file * FP, struct poll_table_struct * table) This function is used within the system call select to hook the current file pointer to the wait defined inside the

First, open the target device. Second, set the sigio Signal Processing for the target device. Program . Third, you need to call the fcntl system to make the current process the master of the file. (In this way, the signal in the file can be used To

1. drop_caches The following descriptions are available in documentation/sysctl/vm.txt: Drop_caches Writing to this will cause the kernel to drop clean caches, dentries and inodes from memory, causing that memory to become free. To free

I installed Ubuntu Linux (wubantu) 6.10 recently. Wow, it's really convenient. My computer is a GB motherboard of MSI. I don't have to worry about what graphics card or sound card it is when I install it, what network adapter, what motherboard, what

I think that as an embedded Linux developer, we should be very familiar with several open-source projects: 1 D-Bus 2 gstreamer3 gconf4 gnome power manager5 mesa6 libxml7 evolution8 gimp9 gnome VFS takes a few months or even a year to analyze,

1. Add the path of the arm-linux-androideabi-addr2line executable file in ndk to the configuration file ~ /. Bashrc, for example: Export Path = $ path :~ /Dlna/android-ndk-r6b/toolchains/arm-linux-androideabi-4.4.3/prebuilt/linux-x86/bin 2. Make

Header file # include     Load dynamic library Void * dlopen (const char * filename, int flag ); Possible flag values: L rtld_lazy L rtld_now L rtld_global L rtld_local L rtld_nodelete (since glibc 2.2) L rtld_noload (since glibc 2.2) L

1. Basic Concepts • 80211: used to manage the configuration of wireless devices. Works with fullmac, mac80211, and nl80211. (Kernel state) • Mac80211: A driver developer can use to write a driver to a softmac wireless device ). • Nl80211: used for

 Memory File System (Linux, FreeBSD)In Linux, part of the memory can be used as a partition, which is called ramdisk. For frequently accessed files that are not changed, you can place them in the memory through ramdisk to significantly improve the

Linux uses four stacks: 1) stack temporarily used during system initialization; 2) There is only one stack (kernel stack) for the kernel program to use. It is located at a fixed position in the system address space and is also the user State stack

  I. df commandDF comes from the coreutils software package and comes with it during system installation. We can use this command to view the disk usage and the location where the file system is mounted. For example: [Root @ localhost beinan] #

Document directory 2.1 key data interfaces between layers 1. wireless network drive (ath9k_htc) Ath9k_htc is a softmac wireless network adapter based on USB interfaces. To ensure that the driver works properly, you must first call usb_register to

1. ipv80211_init • The 80211_wq work queue mainly handles the following tasks: 1) clear: wireless_dev.cleanup_work2) scan: 201780211_registered_device.scan_done_wk3) Event: Listen 80211_registered_device.event_work • Register Netlink with the name "

1. Linux wait 1) function: wait until the sub-process is interrupted or terminated2) header files# Include # Include 3) Function Definition: pid_t wait (int * status );4) Function DescriptionWait () temporarily stops the execution of the current

1. Function Description Pipe (pipeline creation ):1) header file # include 2) define the function: int pipe (INT filedes [2]);3) Function Description: pipe () creates an MPS queue and returns the file description words from the filedes array.Filedes

Use of Linux-driven spin locks // Hello. C # DEFINE _ no_version _ # include # Include # Include # Include #

: Http://sourceforge.net/projects/jnotify/The usage instructions of jpolicyare as follows:Jnotify works on Linux with inotify support (tested on 2.6.14), Mac OS X 10.5 or higher (tested on 10.6.2 ), and on Windows XP/2 k/NT (tested on XP and on

  In Maemo Terms used and defined in: AbiThe application binary interface mainly provides the interface at the target code level. Describes the underlying interfaces between an application and an operating system, between an application and its

At present, there are many Linux mobile phone platforms, no matter whether they are strong or weak at present, let's put them aside first; Let's take a look at the similarities and differences between the technical points used in each platform, such

Because jpgraph is used in PHP, TTF is required. Install freetype1.x. Freetype1.3.1 cannot be compiled. The error is as follows.Ftdump. C: 172: 1: pasting "." and "glyph_object" does not give a valid preprocessing tokenFtdump. C: 182: 1: pasting "."