Standard streams (ITI8510)
|Real-Time Operating Systems and Systems Programming|
|[ @ ]|
This exercise is about standard streams. While we will return to the specific inputs, it is vital to understand how the streams work for most of the exercises.
- Write a program named show_input which reads file 'input.txt' ( fopen(), fread(), fclose() ) and displays it to the standard output (use fwrite() or fprintf instead of printf() and use stdout stream for output).
- Write a program named my_cat which reads from stdin and then outputs each line to stdout using only fgetc() and fputc() functions.
- Find a way to use the program to:
- Show a text file
- Copy a file
- Create and edit a text file
- These tasks are simple enough to figure out without getting off-the-shelf answer from google. Your brain will thank you. If you still want to copy example code -- do it by hand at least. It's pointless waste of your own time to copy-paste and fix code you found online.
- You have variables named stdin, stdout and stderr which correspond to streams which the system opens for you upon program launch. They arrive with inclusion of stdio.h.
- Standard streams can be redirected on the command-line using < > 2> and | signs. You should know them, so find out what they do. A useful keyword is "linux pipes".
- If the task seems too simple: try the Nonblocking IO version of the my_cat utility.