CSCI 1120 (Low-Level Computing):
Sample Programs

Disclaimer: Code linked from this page is intended as a cleaned-up and commented version of examples from class. Many programs could be further improved with regard to functionality or design, but then they would no longer be as close to what we did in class.

Programs

• "Hello, world" program (08/24): hello.c.
• Very simple example of variables, I/O, etc. (08/31): simple-io.c.
• Simple example of conditional execution (09/07): conditional.c.
• Simple example of functions (09/07): functions.c.
• Simple example of while loop (9/14): whilesum.c.
• Simple example of for loop and array(9/14): sillyfor.c.
• Starter sort program (9/14, with revisions): sort-starter.c.
• Simple example of function using pointer parameters (9/21) divide.c.
• Simple example of for loop and array, revised to show some pointer-related things (9/21) sillyfor2.c.
• Simple example of using strings (9/21) simple-strings.c.
• Less trivial example of using strings -- palindrome function (9/28) palindrome.c.
• Program to echo command-line arguments (9/28) echoargs.c.
• I/O examples (10/05): countchars.c, countchars-fromfile.c, whilesum-fromfile.c.
• Program to test sort function, revised to get number of elements from command-line argument and use qsort for sorting (10/12): sort-improved.c.
• Program illustrating how sizes of data types can vary (10/12): sizes.c.
• Makefile example (10/19): Source code files and Makefiles here.
• Linked-list example (10/26, 11/02): Source code files and Makefile here.
• "Floating point is strange" examples (11/09): strange-float-1.c, strange-float-2.c.
• Multithreading examples (11/16):
  • "Hello world" examples hello.c (POSIX threads), hello.c, (OpenMP).
  • Numerical integration examples num-int-seq.c (sequential), timer.h (timing function), num-int-par.c (POSIX threads version), num-int-par.c (OpenMP version).
  • Makefiles for compiling these examples Makefile (sequential), Makefile (POSIX threads), Makefile (OpenMP).
• ncurses examples (11/30, very briefly):
  • Simple self-contained examples: hello.c, center-lines.c, echo-key.c.
  • Library functions for use with remaining programs, and more examples using them: mylib.h, attrib.c, colors.c.
  • Text version of Conway's game of life: conway.c.
  • Example of using menus: menu-example.c.
  • Makefiles: Makefile, Makefile-base, Makefile-depend.

Other files

• Script to mail files for homework submission mail-files. To use this script, put a copy in your directory (simplest thing is to save it with "save page" from a browser) and use the command chmod u+x mail-file to make it "executable". You can then use it to mail me one or more files containing source code. If you put the script in the same directory as your files to send, you can just type

  	mail-files pgm1.c pgm2.c ....
  	

  or if you put the script in your main (home) directory, replace mail-files with ~/mail-files. It prompts for homework number and text to include as the body of the message, and sends a Cc of the message to your username at trinity.edu.
• Sample makefile Makefile for compiling C programs. Note: To obtain a makefile, use your browser's download function; cutting and pasting will likely turn the tabs in the makefile into spaces and cause it to not work. Put the makefile in the directory in which you want to compile. All the makefiles linked from this page begin with brief documentation on their use (the "usage examples").
• Script to compile C program with recommended options compile-c. To use this script, put a copy in your directory and use chmod u+x to make it executable. Then you can type compile-c followed by the name of your source file to compile with recommended options and create an executable with a name based on the sourcefile name (e.g., hello from hello.c.