File Attributes (ITI8510) - Redigeerimiste ajalugu

Irve: /* Hints */

2014-10-22T20:50:21Z

Hints

←Vanem redaktsioon		Redaktsioon: 22. oktoober 2014, kell 22:50
19. rida:		19. rida:
	* You can get the file attributes using [http://linux.die.net/man/2/stat man stat()] function.		* You can get the file attributes using [http://linux.die.net/man/2/stat man stat()] function.
	* The owner permissions are easier to understand using [http://linux.die.net/man/2/chmod man chmod()] (or man stat in the terminal), which provides you with the list of constants which can be compared using if and & to check for the particurlar permission.		* The owner permissions are easier to understand using [http://linux.die.net/man/2/chmod man chmod()] (or man stat in the terminal), which provides you with the list of constants which can be compared using if and & to check for the particurlar permission.
	* File is hidden ~~when~~ it starts with a dot.		* File is hidden if it starts with a dot.
	* For the directory you can use [http://linux.die.net/man/3/opendir opendir()] and [http://linux.die.net/man/3/readdir readdir()] functions.		* For the directory you can use [http://linux.die.net/man/3/opendir opendir()] and [http://linux.die.net/man/3/readdir readdir()] functions.

Irve – 23. oktoober 2013, kell 18:09

2013-10-23T18:09:45Z

←Vanem redaktsioon		Redaktsioon: 23. oktoober 2013, kell 20:09
6. rida:		6. rida:
	Write a program, which takes a filename as an argument and then tries to show the attributes of the file: basically calls the stat() function.		Write a program, which takes a filename as an argument and then tries to show the attributes of the file: basically calls the stat() function.

	When the file is a directory, the program shows the files in that directory (don't show hidden files). When the user runs the program without extra arguments, just show the contents of the working directory. For symbolic links, show the ~~contents of~~ the target.		When the file is a directory, the program shows the files in that directory (don't show hidden files). When the user runs the program without extra arguments, just show the contents of the working directory. For symbolic links, show the data about the target, not the link itself.

	Only show these attributes:		Only show these attributes:

Irve – 23. oktoober 2013, kell 18:09

2013-10-23T18:09:27Z

←Vanem redaktsioon		Redaktsioon: 23. oktoober 2013, kell 20:09
6. rida:		6. rida:
	Write a program, which takes a filename as an argument and then tries to show the attributes of the file: basically calls the stat() function.		Write a program, which takes a filename as an argument and then tries to show the attributes of the file: basically calls the stat() function.

	When the file is a directory, the program shows the files in that directory (don't show hidden files). When the ~~filename is missing~~, show the contents of the working directory. For symbolic links, show the contents of the target.		When the file is a directory, the program shows the files in that directory (don't show hidden files). When the user runs the program without extra arguments, just show the contents of the working directory. For symbolic links, show the contents of the target.

	Only show these attributes:		Only show these attributes:

Irve – 23. oktoober 2013, kell 16:45

2013-10-23T16:45:34Z

←Vanem redaktsioon		Redaktsioon: 23. oktoober 2013, kell 18:45
6. rida:		6. rida:
	Write a program, which takes a filename as an argument and then tries to show the attributes of the file: basically calls the stat() function.		Write a program, which takes a filename as an argument and then tries to show the attributes of the file: basically calls the stat() function.

	When the file is a directory, the program shows the files in that directory (don't show hidden files). When the filename is missing, show the contents of the ~~open~~ directory. For symbolic links, show the contents of the target.		When the file is a directory, the program shows the files in that directory (don't show hidden files). When the filename is missing, show the contents of the working directory. For symbolic links, show the contents of the target.

	Only show these attributes:		Only show these attributes:

Irve: Uus lehekülg: '{{iti8510}} ''We practice using structures in standard library and read file information'' == Task == Write a program, which takes a filename as an argument and then tries to ...'

2013-10-23T16:36:04Z

Uus lehekülg: '{{iti8510}} ''We practice using structures in standard library and read file information'' == Task == Write a program, which takes a filename as an argument and then tries to ...'

Uus lehekülg

{{iti8510}}
''We practice using structures in standard library and read file information''

== Task ==

Write a program, which takes a filename as an argument and then tries to show the attributes of the file: basically calls the stat() function.

When the file is a directory, the program shows the files in that directory (don't show hidden files). When the filename is missing, show the contents of the open directory. For symbolic links, show the contents of the target.

Only show these attributes:
* File size
* Can the owner read?
* Can the owner write?
* Can the owner execute?

== Hints ==

* File existence can be checked with function [http://linux.die.net/man/2/access access()].
* You can get the file attributes using [http://linux.die.net/man/2/stat man stat()] function.
* The owner permissions are easier to understand using [http://linux.die.net/man/2/chmod man chmod()] (or man stat in the terminal), which provides you with the list of constants which can be compared using if and & to check for the particurlar permission.
* File is hidden when it starts with a dot.
* For the directory you can use [http://linux.die.net/man/3/opendir opendir()] and [http://linux.die.net/man/3/readdir readdir()] functions.

=== A Philosophical Detour ===

You may note that the file size attribute has off_t as a type. How to print its contents? Which character should one use with % sign for printf()?

Since off_t can depend on the system, the most rational choice would be to print an unsigned long int and to convert off_t into the corresponding long int using a (''cast'').