Learning unix and C slide

1 Learning Unix and C Software Project – Winter 2007 / 2008 2 Administration 3 Teaching Assistant  T.A.: Michal Ozery-Flato  E-mail: ozery@post.tau.ac.il  Office Hours: by appointment  Location: Schreiber 223  T.A. Website: http://www.cs.tau.ac.il/~ozery/courses/soft-p roject08/ 4 The goals of the course  Learn C  Learn (a bit) Unix  Practice software development:  Understanding software requirements  Implementation  Testing  Deployment (i.e. installation, setting permission, verification)  Working in small teams (submission is in pairs) 5 Course grade  Final grade is based on:  Exam  Assignments and final project:  “Black box” tests: automatic tests that run the program and check its output  “White box” tests: code review 6 Overview (for the rest of this lesson)  Introduction to Unix  Development environments for C  Basic tools in UNIX  Eclipse  Visual Studio  Submission of assignments and project 7 Introduction to UNIX (and Linux…) 8 Operating Systems  An operating system (OS) is a software that:  manages the resources of a computer: CPU, memory, devices  provides programmers and users with an interface to access those resources.  may support/provide: multi-tasking, multi- users, GUI, security, etc.  Interfaces:  Shell: a user interface based on a command-line interpreter. Users Application User Interface Program User Interface OS Kernal Hardware 9 The Unix OS  Unix: multi-user, multi-tasking OS; open source.  History:  1969 – Initial version by Thompson & Ritchie at AT&T Bell Labs.  70’s – Rewritten in C (enables portability).  80’s – System-V (AT&T) and BSD (Berkeley) versions.  90’s – Linux by Linus Torvalds.  For basic introduction and commands - see course web-page (unix.doc) 10 Basic commands in Unix shells Command Short explanation ls -l prints the content of a directory pwd prints the name of the current directory cd change directory mkdir creates a new directory cp copies a file mv moves a file/directory rm removes (deletes) a file rmdir removes an empty directory man help (manual) on a command [...]... the printing function (declared in stdio.h) 17 C programming process C Libraries Edit Hello .c Compile Source code (High-Level Language) Hello.o Link Object file (Machine Language) Hello Run Hello World! Executable Output 18 Basic tools in UNIX 19 Compiling and linking  Compiling and linking   Only compiling (creating hello.o)   gcc c hello .c Only linking   gcc hello .c –o hello gcc hello.o –o hello... PATH to contain c: \cygwin (or your alternative path) CDT: http://www.eclipse.org/cdt/ No support from course staff / helpdesk for installations 24 Create a new workspace /a/home/cc/students/cs/ozery/soft-proj08 25 Create a new project-1 (Linux lab) 26 Create a new project -2 (Linux Lab) 27 create a new project (windows) 28 Add source file 29 Add makefile (a file named “makefile”) 30 Build the project in... Additional common flags to gcc:   -g – allows debugging -l - linking with external libraries 20 Make and makefiles (in short)   makefile: a collection of rules to make targets make: a utility that “executes” makefiles target name dependencies command all: hello clean: -rm hello.o hello hello: hello.o gcc -g hello.o -o hello hello.o: hello .c gcc -c -g hello .c rule Makefiles will be covered... – write permission x – execute (file)/ can cd (directory) changing permissions: chmod   chmod go+rx a.out chmod –R 755 mydir 12 Editing text files in Unix  Common text editors:   vi, vim   pico - simple but very basic, similar to notepad emacs, xemacs (GUI) - see course webpage for a simple tutorial More info: man pico, man vi, man vim man emacs 13 Pipes and redirections to/from files  Pipe:... “makefile”) 30 Build the project in each save (LINUX Lab) 31 Project properties (windows) 32 Build the project 33 Running and Debugging (LINUX lab)  Right click on the executable file (with the bug icon ):    Run As->Local C/ C++ Application Debug As->Local C/ C++ Application Set debugger to “GDB Debugger” 34 Debugging under Windows+cygwin Console in a new window 35 Microsoft Visual Studio 36 ... from 1.in and writing to 1.out diff my1.out 1.out –compares files line by line Ignoring all whitespaces: diff –w my1.out 1.out 15 Development environments for C 16 Printing "Hello World” in C #include Include the standard Include the standard function declaration function declaration int main(void) { printf(“Hello world!\n”); return 0; } Call the printing function (declared in stdio.h) Call the...Additional Unix commands  cat – concatenate files and print to standard output       less – file viewer (“less” is better than “more”) which – locate a command groups – prints the groups the user in (permission ) grep – prints lines matching to a pattern       grep –i “.*lib.*” foo.bar find – search for a file in a directory   cat file1 cat file1 file2 file3 find –name... in the course In the meanwhile, makefiles will be supplied 21 gdb – the GNU debugger  Running gdb: gdb  Useful commands: help, quit, n, s, b / 22 Eclipse 23 Availability  Installed in the CS School LINUX lab (Linux)   Including C/ C++ projects Working at home (Windows)   Code requires porting to LINUX Relatively complicated installation  Cygwin: http://www.cygwin.com/ ... find –name “*.txt” –print find ~/ –name “*.o” -exec rm {} \; clear – clears the terminal screen finger – prints information about a user who – shows who is logged in whoami – identifies the current user 11 File and directory permissions in Unix permissions  permissions = bits 2-10 (bit 1: “d”=directory, “-” = file)      bit 1 = whether is a directory (d) or not (-) bits 2-4: owner permissions... output of prog1 is redirected to the input of prog2   Output redirection to file      Example: ls –l | less prog > foo.out :may cause an error if foo.out exists prog >! foo.out :truncates foo.out if exists prog >> foo.out :may cause error if foo.out does NOT exist prog >>! foo.out :does not check whether foo.out exists Input redirection (read from file)  prog < foo.in 14 Comparing files (program . Language) Object file (Machine Language) Executable Output 19 Basic tools in UNIX 20 Compiling and linking  Compiling and linking  gcc hello .c –o hello  Only compiling (creating hello.o)  gcc c hello .c  Only. (unix. doc) 10 Basic commands in Unix shells Command Short explanation ls -l prints the content of a directory pwd prints the name of the current directory cd change directory mkdir creates a new directory cp. in C #include <stdio.h> int main(void) { printf(“Hello world! ”); return 0; } Include the standard function declaration Include the standard function declaration Call the printing function