洋腔洋调

Unix诞生于美国贝尔实验室,被广泛用于Internet通信软件协议的开发。 Unix程序员们将1970年1月1日的第一秒作为“时间零点”,然后将文件生成时刻的时间减去“时间零点”,所得的秒数作为此文件的存储号。由于Unix使用32位数字来存储“秒数”,所以系统最多只可存储超过时间零点的42亿5千万秒,也就是说Unix的系统时间只能标识到国际标准时间2038年1月19日上午3点14分7秒。到那时,金融、航空、Internet等所有基于Unix的系统都会发生故障,系统又会回到1970年重新计时,这将是又一个灾难性的时刻。     

浅谈Unix环境下的程序和业务数据安全性

基于Unix环境下，从业务操作、程序维护、进库处理三个方面，对应用系统的程序文件和业务数据的风险防范进行了分析。     

Unix系统的shell语言

一、引言 Unix系统问世以来,已取得极大成功。这固然是由于该系统的核心部分—Unix操作系统有许多突出的优点。但作为操作系统与用户间接口的命令程序设计语言shell也起了不可忽视的作用。shell作为操作系统的命令语言,使用户可以利用终端或从命令文件调用操作系统所提供的功能。shell本身又像高级程序设计语言一样,具有变量,控制流程(if-     

基于RPC的分布式计算的实现

讨论Unix系统下基于RPC的分布式计算的实现问题，包括XDR数据交换,Server与Client程序设计、多线程与多进程RPC调用。     

如何编写Unix的daemon程序

该文主要探讨了在系统V/386 Unix中如何编写有效的daemon(幽灵)程序,文中给出了编写daemon程序的一些注意事项,介绍了daemon进程的几种启动方式,对unix用户和系统程序员编写正确的daemon程序有一定的借鉴作用。     

动态截取Unix系统主控屏幕文本的方法

提出了一种解决在Unix系统下。动态截取屏幕问题的思路及方法，并开发程序给予实现。     

中英文兼容的屏幕编辑程序的实现

vi屏幕编辑程序是Unix系统中最为常用的实用程序之一.本文概述了vi程序的运行环境、汉化的目的及意义,并围绕在汉化vi程序中所遇到的10个主要问题逐步展开讨论并概述了实现方法.     

向企业扩展NT集成系统 DEC搬出ALL Connect程序

继向企业提供Microsoft Windows NT解决方案之后,DEC公司宣布ALL Connect程序。它扩展了Windows NT服务器的企业工作站解决方案,实现了DEC的Unix和Windows NT的互操作性。 DEC通过将ALL Connect程序用于Unix,提供了接通Unix和Windows NT环境必须的关键部件:Windows NT支持,强有力的     

LKM"后门"随想

现在的操作系统一般都支持LKM(Loadable Kernel Module)可加载内核模块。可能在不同的系统中对应的名字不一样,但实现的机制相差不远,都是为了实现少占资源而又灵活地配置系统。在微软平台下有.dll、.vxd、.sys等一些可加载的程序,在Unix或类Unix平台下一般都是一些/lib下的.so文件。虽然这些程序被放到内存中后并不主动地去做任何事情,而是等待触发事件,但这些程序却始终处于操作系统的核心态,拥有至高无上的权限。对于入侵者来说,这比获得一个Administrator或     

五月新书

莱昂氏 Unix源代码分析 (中文版 )Lion's Commentary on Unix6th Edition with Source Code(澳大利亚 ) John L ions著 ,尤晋元译 /原出版商 :Peer- to- Peer,1996 / 16开 ,约 6 0元简目 :上篇 U nix第 6版内核部分的完整源代码 ;上篇莱昂氏 Unix源代码分析 1绪论 ;2基础知识 ;3阅读“C”程序 ;4概述 ;I初始化、进程初始化 ;5两个文件 ;6系统初启 ;7进程 ;8进程管理 ;II陷入、中断和系统调用、进程管理 ;9硬件中断和陷入 ;10汇编语言“trap”例程 ;11时钟中断 ;12陷入于系统调用 ;13软件中断 ;III程序交换、基本输入 /输出、块设备 …     

The Unix System and Software Reusability

The Unix system contains a variety of facilities that enhance the reuse of software. These vary from the utterly conventional, such as function libraries, to basic architectural mechanisms, such as the Unix pipe. The Unix pipe, which makes whole programs building blocks of larger computational structures, has been the primary reason for the development of a literature of useful, but specialized programs-programs that would be too costly to write in a conventional programming language such as C. It has led to high levels of program reuse both by the nature of its operation and through its effect on programming conventions (e.g., programs structured as simple filters). Another facility enhancing reuse on Unix is the on-line C source code for Unix system programs. This has led to a shared style of programming in which existing programs are used as models for new programs, allowing the reuse of ideas, algorithms and source code. Finally, the Unix system contains many other reuse enhancing facilities, such as generic facilities for screen management (curses and termcap) and program generators (lex and yacc).     

The program animation system PASTIS

The software animation system PASTIS (Program Animation System with Interactive Solutions) for program animation with emphasis on the visualization of the dynamic behaviour of algorithms and data structures is presented. Its main properties are unmodified source code of the visualized program, concurrent multiple views on algorithms and data structures, and interactive alterations of views during run time. PASTIS is distinguished by high modularity and strict separation of its components. This makes it particularly suitable for distributed computing environments. The interface between program and animation is a relational data model. Animations are directed by a single tuple, or sets of tuples, called relations, or sets of relations, called networks. Animations can be nested hierarchically. A prototype of PASTIS was implemented under Unix

1 Unix is a trademark of AT&T.

using the GNU source level debugger gdb and the X-window system.     

A noninterference monitoring and replay mechanism for real-timesoftware testing and debugging

A noninterference monitoring and replay mechanism using the recorded execution history of a program to control the replay of the program behavior and guarantee the reproduction of its errors is presented. Based on this approach, a noninterference monitoring architecture has been developed to collect the program execution data of a target real-time software system without affecting its execution. A replay mechanism designed to control the reproduction of the program behavior as well as the examination of the states of the target system and its behavior is presented. The monitoring system has been implemented using a Motorola 68000 computer in a Unix system environment. An example is used to illustrate how the mechanism detects timing errors of real-time software systems     

Unix下企业级安全WebMail系统的设计与实现

构建了一套以FreeBSD4.9 Unix作为底层操作系统，Qmail作为MTA程序，MYSQL为数据库，C++作为开发工具，具有高可靠性、易安装、易管理、易维护、安全高效、性价比高的可行性电子邮件服务器系统。该系统目前已投入到企事业单位的实际应用中，具有良好的市场应用前景。     

A language and system for the construction and tuning of parallel programs

The programming of efficient parallel software typically requires extensive experimentation with program prototypes. To facilitate such experimentation, any programming system that supports rapid prototyping of parallel programs should provide high-level language primitives with which programs can be explicitly, statically, or dynamically tuned with respect to performance and reliability. Such language primitives should be able to refer conveniently to the information about the executing program and the parallel hardware required for tuning. Such information may include monitoring data about the current or previous program or even hints regarding appropriate tuning decisions. Language primitives and an associated programming system for program tuning are presented. The primitives and system have been implemented, and have been tested with several parallel applications on a network of Unix workstations.<>     

Unix软件平台用于实时监控系统的研究

提出并讨论了Ｕｎｉｘ操作系统适用于监控系统的特点,并提出了对Ｕｎｉｘ进行实时化改造的方案以及对系统进行性能测试的工具,经过实时化改造后,Ｕｎｉｘ系统不失为实时监控系统的首选平台。     

Subjective impressions of a non-naïve Unix and c beginner

This paper details an experienced programmer's first impressions of working with the Unix operating system and c programming language. Use of the Unix shell, vi editor, c compiler and some utilities are discussed, as are the Unix documentation and some relevant textbooks. An assessment of the difficulties and advantages of starting with Unix is given.     

基于知识库的Unix主机配置安全审计软件的设计与实现

配置安全审计是保证Unix主机安全的重要措施,并进一步为Unix操作系统所承载的业务应用提供了安全保障。本文首先分析Unix操作系统的配置安全和传统的配置安全审计方法,并针对传统方法的不足,提出一种基于可灵活配置的知识库实现Unix操作系统配置安全审计软件的设计方案,最后给出这种方案的具体实现。     

Internet网络环境的测试程序设计与实现

在ＩＣＭＰ及ＩＰ协议下,讨论了基于Ｕｎｉｘ环境的任务客户端,通过Ｉｎｔｅｒｎｅｔ网络环境是否可任何服务器端的测试程序设计,主要介绍了利用ｓｏｃｋｅｔ接口客户端测试程序的设计与实现。     

A visual process connector for Unix

Upconn a tool that lets Unix programmers visually describe the connections between the processes in a distributed program and then execute the distributed program, is described. Upconn consists of several modules and can be extended by adding to a library of tools rather than by adding many special features to Upconn itself. Upconn has three main uses. First, it lets researchers study distributed processing in common Unix environments, reducing the dependence on specialized environments. Second, it can be used for rapid prototyping of distributed applications. Third, Upconn is a learning tool that can help students focus on writing distributed programs without dealing with the complexities of the communication links