Stage 1: Initialising a C struct and printing it out as text [3 marks]

In this stage you will declare a C data structure, create an instance of it and statically initialize it

(declare it as a static or global variable and initialise it in one statement using braces). You will then

print out the instance. This stage develops the following specific skills:

? Declaring a C struct.

? Initialising a C struct

? Printing various data types using printf

Note: Do not use bit fields in your struct. All the data types that are specified correspond to

ordinary C data types.

Note: The automarker checks your struct definition against expected ways of writing it and

awards marks for correctness. Field names must be exactly correct. Types should be the common C

language data types as defined in ANSI C.

Resources

The following documents on iLearn may be helpful:

? Compile, Run, Make C Programs on Linux

? C Programming Notes for Data File Lab

Your downloaded stage1.tar file contains the following files:

? filestruct-description.txt: A simple description of the fields that are in your

struct – their names and type description.

? initialisation-specification.txt: Specifies the initial value for each field of

your struct. The initial value has to be formatted in a specific way in your source code – this

may mean that you have to convert one representation to another. See the lab note

Decimal, Binary, Octal and Hex. Note: It makes no difference to the data that is stored inside

the computer whether you initialise the field with decimal or the equivalent hexadecimal or

octal. However, as an exercise, we require you to make the appropriate type conversions

and the automarker will check your code.

? expected-output.txt: Stage 1 expected output file. Use the example in this file to

work out what formatting options to use in printf.

Useful Unix commands

You might find the following Unix system commands helpful.

? cat

? diff

Task

Write a C program that declares your particular data structure as described in the C structure

description file. Statically initialise an instance of the data structure to the initial values as specified

in the file – use the data formats as specified in the file such as hexadecimal, decimal or octal

constants. In the main program, print out the data structure using printf formatting to make it

exactly match the provided sample output file. Note that you may need to use various formatting

options with printf to control the appearance of the output. You are expected to read about

printf and work out how to format the data so that it exactly matches the expected output.

Submit your program for automatic assessment using the lab command. Your program style may

be assessed according to the coding standards in the documents Some Important Comments on Code

Style and Systems Programming Style which are available on iLearn.