Program name | get_next_line |
---|---|
Prototype | int get_next_line(int fd, char **line); |
Turn in files | get_next_line.c, get_next_line_utils.c, get_next_line.h |
Parameters | #1. file descriptor for reading #2. The value of what has been read |
Return value | 1 : A line has been read0 : EOF has been reached-1 : An error happened |
External functs. | read , malloc , free |
Description | Write a function which returns a line read from a file descriptor, without the newline. |
- Calling your function get_next_line in a loop will then allow you to read the text available on a file descriptor one line at a time until the
EOF
. - Make sure that your function behaves well when it reads from a file and when it reads from the standard input.
- libft is not allowed for this project. You must add a get_next_line_utils.c file which will contain the functions that are needed for your get_next_line to work.
- Your program must compile with the flag -D BUFFER_SIZE=xx. which will be used as the buffer size for the read calls in your get_next_line. This value will be modified by your evaluators and by moulinette.
- Compilation will be done this way : gcc -Wall -Wextra -Werror -D BUFFER_SIZE=32 get_next_line.c get_next_line_utils.c
- Your read must use the
BUFFER_SIZE
defined during compilation to read from a file or from stdin. - In the header file get_next_line.h you must have at least the prototype of the function get_next_line.
NOTE: Does your function still work if the BUFFER_SIZE value is 9999? And if the BUFFER_SIZE value is 1? And 10000000? Do you know why?
NOTE: You should try to read as little as possible each time get_next_line is called. If you encounter a newline, you have to return the current line. Don’t read the whole file and then process each line.
NOTE: Don’t turn in your project without testing. There are many tests to run, cover your bases. Try to read from a file, from a redirection, from standard input. How does your program behave when you send a newline to the standard output? And CTRL-D?
- We consider that get_next_line has an undefined behavior if, between two calls, the same file descriptor switches to a different file before
EOF
has been reached on the first fd. lseek
is not an allowed function. File reading must be done only once.- Finally we consider that get_next_line has an undefined behavior when reading from a binary file. However, if you wish, you can make this behavior coherent.
- Global variables are forbidden.
HELP: A good start would be to know what a static variable is.
The project get_next_line is straightforward and leaves very little room for bonuses, but I am sure that you have a lot of imagination. If you aced perfectly the mandatory part, then by all means complete this bonus part to go further. I repeat, no bonus will be taken into consideration if the mandatory part isn’t perfect. Turn-in all 3 initial files with _bonus for this part.
- To succeed get_next_line with a single static variable.
- To be able to manage multiple file descriptor with your get_next_line. For example, if the file descriptors 3, 4 and 5 are accessible for reading, then you can call get_next_line once on 3, once on 4, once again on 3 then once on 5 etc. without losing the reading thread on each of the descriptors.