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For beginners who want to learn about Linux file permissions, here’s a stupid simple application that can help.<\/p>\n
It’s Concessio<\/a>, a free open-source app designed for GNOME, though works in most Linux through Flatpak package.<\/p>\n <\/p>\n As you know, every file and folder in Linux has a specific set of permissions. It controls the read<\/b>, write<\/b>, and execute<\/b> permissions for user<\/b> (who own the file\/folder), group<\/b> (group of users share access to the file\/folder), and others<\/b> (all other users in system).<\/p>\n Permissions can be represented by either numbers or a string of characters.<\/p>\n The permissions for a file\/folder can be represented by a string of 10 characters, e,g., -rwxr-xr–<\/b>. The first means directory (d<\/b>) or not (–<\/b>), the 2 ~ 4 characters for user, 5 ~ 7 for group, and the last 3 (8 ~ 10) characters for others.<\/p>\n It can also be represented by 3 numbers, e.g., 755. the first for user (owner), second for group, and the last for others. And, it can sometimes be 4 numbers due to special permissions.<\/p>\n Understanding Linux file permissions is essential for all Linux administrators. But I often forgot the numerical representation.<\/p>\n To make it clearer to understand, the Concessio provides a simple interface that user can either click the book, pencil, play (execute) icons to set a permissions combination and see the numeric and symbolic representations, or input the permission numbers or characters and convent to each others.<\/p>\n As you see, it can also show special permissions in numeric and symbolic representations. They include:<\/p>\n With version 0.3.0, the app added support umask page, that can help to determine the default permissions for newly created files and directories.<\/p>\n Besides umask, symbolic, and numeric representations, Concessio also support opening a file to see its permission and provides a help page that explains the Linux file permissions with text and examples.<\/p>\n Concessio is available to install in most Linux through Flatpak package<\/a>.<\/p>\n Fedora (with 3rd repository enabled) and Linux Mint since 21 can simply search & install it from either GNOME Software or Software Manager.<\/p>\n While other Linux can follow the steps below one by one to get it:<\/p>\n\n
r--<\/code> or 4<\/b> + 0 + 0.<\/li>\n-w-<\/code> or 0 + 2<\/b> + 0.<\/li>\n--x<\/code> or 0 + 0 + 1<\/b>.<\/li>\nrw-<\/code> or 6<\/b> (4+2+0)<\/li>\nr-x<\/code> or 5<\/b> (4+0+1)<\/li>\n-wx<\/code> or 3<\/b> (0+2+1)<\/li>\nrwx<\/code> or 7<\/b> (4+2+1).<\/li>\n<\/ul>\n![\"\"](\"https:\/\/ubuntuhandbook.org\/wp-content\/uploads\/2026\/03\/terminal-filepermissions-700x468.webp\")
<\/a><\/p>\n![\"\"](\"https:\/\/ubuntuhandbook.org\/wp-content\/uploads\/2026\/03\/concessio-1-700x487.webp\")
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<\/a><\/p>\n![\"\"](\"https:\/\/ubuntuhandbook.org\/wp-content\/uploads\/2026\/03\/concessio-help-700x487.webp\")
<\/a><\/p>\nInstall Concessio<\/h3>\n