bdi signal

The trap command is used to specify the action to be taken after the signal is received. A common use is to complete the cleanup when the script is interrupted. However, this time I met it because the customer has a requirement: the user who accesses the server from the terminal will automatically run a command after logging on to the server, such as opening the application (the command is written in a file such as. BASHRC, etc.), and finally exiting

The concept of a signalSignal (signal)--the way communication between processes is a software interrupt. Once a process receives a signal, it interrupts the original program execution process to process the signal.Several common signals:SIGINT terminating process interrupt process (CONTROL+C)SIGTERM terminating process software termination signalSIGKILL Terminate process Kill processSIGALRM Alarm Clock sign

View supported signal lists in Linux :~ $ Kill-l1) SIGHUP 2) SIGINT 3) SIGQUIT 4) SIGILL5) SIGTRAP 6) SIGABRT 7) SIGBUS 8) SIGFPE9) SIGKILL 10) SIGUSR1 11) SIGSEGV 12) SIGUSR213) SIGPIPE 14) SIGALRM 15) SIGTERM 17) SIGCHLD18) SIGCONT 19) SIGSTOP 20) SIGTSTP 21) SIGTTIN22) SIGTTOU 23) SIGURG 24) SIGXCPU 25) signature) SIGVTALRM 27) SIGPROF 28) SIGWINCH 29) SIGIO30) SIGPWR 31) SIGSYS 34) SIGRTMIN 35) SIGRTMIN + 136) SIGRTMIN + 2 37) SIGRTMIN + 3 38) SIG

I. Signals and messagesThe signals in Linux have the same energy as the messages below the win, all have a wide variety of signals (messages) and their corresponding signal (message) processing functions.1. Signal processing function added.Signal function.The bottom is copied from advanced programming. The average is not strange, a look will understand.Defined:typedef void Sigfunc (int);Sigfunc *

In graphic interface programming, we often want to notify another or several objects when a visual object changes, we hope that any class of objects can communicate with other objects. For example, a value display window is used to display the current value of a scroll bar object. When the value of the scroll bar object changes, we hope that the value display window will receive a "value change" signal from the scroll bar object to change its display

There is no big difference between a slot function and a normal C + + member function. They can also be virtual, can be overridden, can be public, protected, or private, can be called by other C + + functions, and arguments can be of any type. If you want to say the difference, that is, the slot function can be connected to a signal, when this signal occurs, it can be automatically invoked. The Connect ()

No network signal solution for Millet 4s mobile phone 1, you are in the environment mobile phone signal is not good to the Internet (basement or subway station is particularly serious). 2, mobile phone software factors caused by the mobile phone can not be online, check whether GPRS open, or mobile phone restart, and sometimes restart the phone will solve the network is not connected to the pr

High speed ADC Clock jitter solution The clock jitter of the high-speed ADC affects the SNR of the high-speed ADC, while the signal-to-noise ratio determines the effective range of the analog front-end input. Therefore, it is necessary to determine the effective input range of the analog front end, then determine the SNR that should be satisfied, and then deduce the clock jitter. First, the relationship between the dynamic input range and the effecti

Introduction to the Flask signal mechanism (signals) in the Python Web framework, flasksignals Signal (signals) The Flask signal (signals, or event hooking) allows a specific sender to notify the subscriber of what happened (since we know what happened, we can know what to do next ). Flask provides some signals (core signals) and other extensions provide more si

SignalDjango provides a "signal dispatcher" that allows decoupled applications to be notified when operations occur elsewhere in the framework. Simply put, a signal allows a specific sender to notify a group of receiver that certain operations have occurred. This is useful in situations where multiple code is associated with the same event.Built-in signal model s

Author: POLink: http://blog.csdn.net/livelylittlefish/article/details/7308100 Content 0. Preface 1. Ngx_init_signals () function 1.1 ngx_signal_t Structure 1.2 Signals array 1.3 Sigaction Structure 2. A few questions How the 2.1ngx_signal_value macro gets the signal value of the integer signo. 2.2 handler=sig_ign=0x1 is how to ignore the signal. 3.ngx_signal_handler () function 4. Summary 0. Preface This p

This is a creation in Article, where the information may have evolved or changed. The system we operate in production requires an elegant exit, that is, after the program receives the exit notification, there is a chance to execute a cleanup code before the finishing touches are finished and then really quits. We use System signal to notify the system to exit, that is, kill Pragram-pid. We set up a processing function for some system signals in the pr

This article comes from A deeper look at signals and Slots,scott Collins 2005.12.19. What we are saying here is that the "signal slot" is not just a signal slot inside the Qt library, but rather a global height that understands the signal slot from a system perspective. So in this article, the Qt signal slot is only in

Signals and slots are an important part of QT programming. This mechanism can associate the actions of objects without mutual understanding. In the previous routines, We have connected the signal and slot, declared the signal and slot of the control, implemented the slot function, and sent the signal. Now let's have a better understanding of this mechanism. The s

1. Signals are soft interrupts that provide a mechanism for handling asynchronous eventsAn asynchronous event can originate from outside the system (for example, user input ctrl-c) or from within the system (for example, except 0) the kernel uses one of the following three methods to process the signal: (1)Ignore this signal。Sigkill and Sigstop cannot be ignored。 (2)capture and process the

This article mainly summarizes the PHP signal management knowledge of the relevant information, the need for friends can refer to the following Sigquit establish core file termination process, and generate core fileSigill Creating a core file illegal directiveSIGTRAP build core file tracking self-trappingSigbus establishing a core file bus errorSIGSEGV creating core file Segment Illegal errorSIGFPE creating a core file floating point exceptionSigiot

I. Common signals: 1. sighup: end signal sent from the terminal 2. SIGINT: the interrupt signal from the keyboard, CTRL + c 3. sigkill: the signal will end the process of receiving the signal. 4. sigterm: signal sent by the kill command 5. sigchld: indicates the

Linux signal programming practices (1)Interrupted Interruption is the system's response to asynchronous events. During code execution, the process can be interrupted at any time and then run the exception handling program; Computer System interruption scenario: interrupt source sends interrupt signal-> CPU determines whether the interrupt is blocked and protects the site-> CPU (query the interrupt vector ta

sensor signal Output YUV, RGB, RAW DATA, JPEG 4 different waysCategory: Camera 2012-12-17 08:59 10085 people read reviews (5) Favorite reports In simple terms,Yuv:luma (Y) + chroma (UV) format, typically sensor supports YUV422 format, that is, the data format is output in y-u-y-v orderRGB: Traditional red-green-blue format, such as RGB565, whose 16-bit data format is 5-bit R + 6-bit G + 5-bit B. G more than one, because the human eye is more sensitive

If you want to perform concurrent access to a function, whether through a thread or through a process, you may encounter problems caused by the unavailability of the function. In this article, we use the sample code to find out what exceptions will occur if the reusability is not guaranteed. Pay special attention to the signal. Five practical programming experiences are introduced, and the proposed compiler model is discussed. In this model, the reusa