Join , subscribers and get a daily digest of news, geek trivia, and our feature articles. By submitting your email, you agree to the Terms of Use and Privacy Policy. The Linux stat command shows you much more detail than ls does. Take a peek behind the curtain with this informative and configurable utility. You can rip up the floorboards and then dig a hole.
You can peel Linux like an onion. To display this information ls reads it from a file system structure called an inode. Every file and directory has an inode. The inode holds metadata about the file , such as which filesystem blocks it occupies, and the date stamps associated with the file. The inode is like a library card for the file. But ls will only show you some of the information. To see everything, we need to use the stat command. Like ls , the stat command has a lot of options.
This makes it a great candidate for the use of aliases. Once you have discovered a particular set of options that make stat give you the output that you want, wrap it in an alias or shell function. The timestamps are timezone sensitive. The at the end of each line shows that this file was created on a computer in a Coordinated Universal Time UTC timezone that is five hours ahead of the timezone of the current computer.
So this computer is five hours behind the computer that created this file. The modify and change timestamps can cause confusion because, to the uninitiated, their names sound as if they mean the same thing. The modified timestamp will only be updated if the contents of the file are changed.
The change timestamp is updated for both content changes and attribute changes. To have stat report on several files at once, pass the filenames to stat on the command line:. To use stat on a set of files, use pattern matching. The -f filesystem option tells stat to report on the filesystem that the file resides on. If you use stat on a file that is actually a symbolic link, it will report on the link. If you wanted stat to report on the file that the link points to, use the -L dereference option.
The file code. The filename shows code. The file size is only 11 bytes. There are zero blocks devoted to storing this link. The file type is listed as a symbolic link. This is now showing the file details for the file pointed to by the symbolic link. But note that the filename is still given as code.
This is the name of the link, not the target file. Access: The last time at which the file was accessed. Modify: The last time at which file was modified. Birth: The time at which the file was created. Displaying the File System Information stat command can provide the file system information when we provide file name with the -f —file-system options. The information we get for the filesystem from the stat File: The name of provided file.
ID: File system ID in hexadecimal format. Namelen: The maximum length number of characters of a file name. Fundamental block size: Total size of each block on the file system. Blocks: Total: Total number of blocks in the file system Free: Total number of free blocks in the file system Available: Total number of free blocks available for non-root users Inodes: Total: Total number of inodes in the file system.
Free: Total number of free inodes in the file system. Using Stat With Multiple File To get the information about multiple files using the stat command, just mention the filenames separated by space: stat locale. Dereference Symlinks If we provide the symbolic link file to the stat command, then it will give the information about the symbolic link instead of the original file. To follow or dereference the symbolic and display information about the file of which the symbolic like point stat provide -L —dereference option.
We can use this option to dereference the symbolic links. There are two ways by which we can customize the output The first is using the -c option or the —format option with the format of the output. The stat can also display the information in the terse form. Generally, the timestamps show the time at which the file was created from the UTC timezone. Here is one note for stat command, your shell may have its own version of the stat.
Here logical and operator is used to print the respective modes. We have checked for permissions for user, group, and others for the specified file file name entered by user.
With this you can see how to use the stat system call from the C programming language to get information from the OS kernel about files. If you have a question feel free tell us via comment section. Ayesha loves to write and make video tutorials on different programming languages.
Ayesha Tariq is a student of Computer Science and working as a freelancer as well. Writing tutorials and creating programs is her passion. She can be found on Facebook at Ayesha Tariq. Linux System Calls System calls provided by the linux kernel are exposed in the C programming language via glibc.
Stat System Call: Stat system call is a system call in Linux to check the status of a file such as to check when the file was accessed. Ayesha Tariq Ayesha loves to write and make video tutorials on different programming languages.
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