Summary

This chapter has given you a fairly thorough introduction to the iostream class library. In all likelihood, it is all you need to create programs using iostreams. (In later chapters you’ll see simple examples of adding iostream functionality to your own classes.) However, you should be aware that there are some additional features in iostreams that are not used often, but which you can discover by looking at the iostream header files and by reading your compiler’s documentation on iostreams.

Exercises

1.Open a file by creating an ifstream object called in. Make an ostrstream object called os, and read the entire contents into the ostrstream using the rdbuf( ) member function. Get the address of os’s char* with the str( ) function, and capitalize every character in the file using the Standard C toupper( ) macro. Write the result out to a new file, and delete the memory allocated by os.

2.Create a program that opens a file (the first argument on the command line) and searches it for any one of a set of words (the remaining arguments on the command line). Read the input a line at a time, and print out the lines (with line numbers) that match.

3.Write a program that adds a copyright notice to the beginning of all sourcecode files. This is a small modification to exercise 1.

4.Use your favorite text-searching program (grep, for example) to output the names (only) of all the files that contain a particular pattern. Redirect the output into a file. Write a program that uses the contents of that file to generate a batch file that invokes your editor on each of the files found by the search program.

Chapter 14: Templates & Container Classes

120