1、 了解系统调用fork()、execl()、exit()、getpid()和waitpid()的功能和实现过程 2、 编写一段程序实现以下功能: a) 使用系统调用fork()创建两个子进程 b) 父进程重复显示字符串”parent:”,并使用函数getpid()显示自己的进程ID。 c) 两个子进程分别重复显示字符串”child:”,并使用函数getpid()显示自己的进程ID 3、 编写一段程序实现以下功能: a) 使用系统调用fork()创建一个子进程 b) 子进程显示自己的进程ID和字符串": The child is calling an exec.\n",然后通过execl()调用系统命令ps显示当前运行的进程情况,从而更换自己的执行代码,最后调用exit()结束。 c) 父进程显示自己的进程ID和字符串” ": The parent is waiting for child to exit.\n ",然后调用waitpid()等待子进程结束,并在子进程结束后显示”The parent exit.\n
上传时间: 2013-12-18
上传用户:叶山豪
This section contains a brief introduction to the C language. It is intended as a tutorial on the language, and aims at getting a reader new to C started as quickly as possible. It is certainly not intended as a substitute for any of the numerous textbooks on C. 2. write a recursive function FIB (n) to find out the nth element in theFibanocci sequence number which is 1,1,2,3,5,8,13,21,34,55,…3. write the prefix and postfix form of the following infix expressiona + b – c / d + e * f – g * h / i ^ j4. write a function to count the number of nodes in a binary tr
标签: introduction the contains intended
上传时间: 2013-12-23
上传用户:liansi
by Randal L. Schwartz and Tom Phoenix ISBN 0-596-00132-0 Third Edition, published July 2001. (See the catalog page for this book.) the text of Learning Perl, 3rd Edition. Table of Contents Copyright Page Preface Chapter 1: Introduction Chapter 2: Scalar Data Chapter 3: Lists and Arrays Chapter 4: Subroutines Chapter 5: Hashes Chapter 6: I/O Basics Chapter 7: Concepts of Regular Expressions Chapter 8: More About Regular Expressions Chapter 9: Using Regular Expressions Chapter 10: More Control Structures Chapter 11: Filehandles and File Tests Chapter 12: Directory Operations Chapter 13: Manipulating Files and Directories Chapter 14: Process Management Chapter 15: Strings and Sorting Chapter 16: Simple Databases Chapter 17: Some Advanced Perl Techniques Appendix A: Exercise Answers Appendix B: Beyond the Llama Index Colophon
标签: L. published Schwartz Edition
上传时间: 2014-11-29
上传用户:kr770906
by Randal L. Schwartz and Tom Phoenix ISBN 0-596-00132-0 Third Edition, published July 2001. (See the catalog page for this book.) Learning Perl, 3rd Edition. Table of Contents Copyright Page Preface Chapter 1: Introduction Chapter 2: Scalar Data Chapter 3: Lists and Arrays Chapter 4: Subroutines Chapter 5: Hashes Chapter 6: I/O Basics Chapter 7: Concepts of Regular Expressions Chapter 8: More About Regular Expressions Chapter 9: Using Regular Expressions Chapter 10: More Control Structures Chapter 11: Filehandles and File Tests Chapter 12: Directory Operations Chapter 13: Manipulating Files and Directories Chapter 14: Process Management Chapter 15: Strings and Sorting Chapter 16: Simple Databases Chapter 17: Some Advanced Perl Techniques Appendix A: Exercise Answers Appendix B: Beyond the Llama Index Colophon
标签: L. published Schwartz Edition
上传时间: 2015-09-03
上传用户:lifangyuan12
Implemented BFS, DFS and A* To compile this project, use the following command: g++ -o search main.cpp Then you can run it: ./search The input is loaded from a input file in.txt Here is the format of the input file: The first line of the input file shoud contain two chars indicate the source and destination city for breadth first and depth first algorithm. The second line of input file shoud be an integer m indicate the number of connections for the map. Following m lines describe the map, each line represents to one connection in this form: dist city1 city2, which means there is a connection between city1 and city2 with the distance dist. The following input are for A* The following line contains two chars indicate the source and destination city for A* algorithm. Then there is an integer h indicate the number of heuristic. The following h lines is in the form: city dist which means the straight-line distance from the city to B is dist.
标签: Implemented following compile command
上传时间: 2014-01-01
上传用户:lhc9102
BNB20 Finds the constrained minimum of a function of several possibly integer variables. % Usage: [errmsg,Z,X,t,c,fail] = % BNB20(fun,x0,xstatus,xlb,xub,A,B,Aeq,Beq,nonlcon,settings,options,P1,P2,...) % % BNB solves problems of the form: % Minimize F(x) subject to: xlb <= x0 <=xub % A*x <= B Aeq*x=Beq % C(x)<=0 Ceq(x)=0 % x(i) is continuous for xstatus(i)=0 % x(i) integer for xstatus(i)= 1 % x(i) fixed for xstatus(i)=2 %
标签: constrained variables function possibly
上传时间: 2014-01-13
上传用户:youth25
acm HDOJ 1051WoodenSticks Description: There is a pile of n wooden sticks. The length and weight of each stick are known in advance. The sticks are to be processed by a woodworking machine in one by one fashion. It needs some time, called setup time, for the machine to prepare processing a stick. The setup times are associated with cleaning operations and changing tools and shapes in the machine. The setup times of the woodworking machine are given as follows: (a) The setup time for the first wooden stick is 1 minute. (b) Right after processing a stick of length l and weight w , the machine will need no setup time for a stick of length l and weight w if l<=l and w<=w . Otherwise, it will need 1 minute for setup.
标签: WoodenSticks Description length wooden
上传时间: 2014-03-08
上传用户:netwolf
Zinc is an object oriented, platform independent, framework for designing graphical user interfaces (GUIs) for cross platform applications. Zinc is scalable and customizable. It provides a full-featured toolkit for the creation of GUIs and event-driven applications.
标签: independent interfaces framework designing
上传时间: 2015-11-28
上传用户:qb1993225
These Simulink blocks contain transfer functions that model the pressure and flow transients for axisymmetric 2D viscous flow of a compressible fluid in a straight rigid circular cross section pipelines. Three models are available: (1) pressures at the ends (2) flow rates at the ends (3) pressure at one end and flow rate at the other Filtering is incorporated to reduce numerical oscillation (Gibbs phenomenon). See J. Dyn. Systems, Meas. & Control vol 122 (2000) pp. 153-162.
标签: transients functions Simulink transfer
上传时间: 2014-01-22
上传用户:Shaikh
DirectX not only provides fast access to the hardware and therefore incredibly speedy performance, but it also makes it much easier for hardware developers to produce new devices that work well in the Windows environment. The DirectX APIs take away the necessity of writing your own low-level, device-specific code to access hardware such as the display adapter and network card, making it much easier for you to write programs that take full advantage of the computer s multimedia capabilities.
标签: performance incredibly therefore hardware
上传时间: 2016-02-16
上传用户:秦莞尔w