Regular Linux files are the files that may include text, data, information, piece of code or program instructions. This flag is widely used by Bash programmers to make the code flow in such a way that tasks get performed only if the file exists. Here, in our case, too, we are checkin...
FILE=/etc/resolv.conf if test -f "$FILE"; then echo "$FILE exists." fi Copy FILE=/etc/resolv.conf if [ -f "$FILE" ]; then echo "$FILE exists." fi CopyFILE=/etc/resolv.conf if [[ -f "$FILE" ]]; then echo "$FILE exists." fi Copy...
For example, to test if the file/tmp/test.logexists, run the following command: test -f /tmp/test.txt The first line executes the test to see if the file exists. The second command,echo, displays the results. The result0means that the file exists, while1means no file was found. ech...
To check for a directory, replace the-foperator (which is used for checking if a file exists or not) with the-doperator. Example 1: A traditional approach Usually, the Bash built-in test operators are used in combination with the if conditional, like I demonstrated above. This has two a...
Now, the empty file has been opened in the nano editor. Within the first line of code, we have initialized a file variable “F” holding a path to a file “new.txt” as “/home/linux/new.txt”. The “if-then” statement of bash has been utilized here to check if the file “new...
Here I will show you how to check if a Linux user exists (or does not exist) in a POSIX-compatible shell like Bash or Dash. I will use thegetentcommand along with the/etc/passwdfile for this. Example Bash script: if getent passwd "$username" >/dev/null; then ...
Example 1: Check the Existence of the File Using the -F Operator with Single Third Brackets ([]) Create a Bash file with the following script that takes the filename from the user and check whether the file exists in the current location or not using the -f operator in the “if” con...
In this example, I will use thegetentcommand to check if a Linux group exists. if getent group "$groupname" >/dev/null; then echo "Group $groupname exists" fi Replace$groupnamewith the name of the group you want to check. If you like to check if the group does not exist (e.g....
option to the test builtin check to see if FILE exists and has a size greater than zero. It returns true and false values to indicate that file is empty or has some data. This page shows how to check if a file is empty in Bash shell running on a Linux or Unix-like operating ...
For example, to check if the /etc/filetocheck directory exists, you can use: NOTE: You can also use double brackets [[ instead of [ single brackets. Check if the file doesn’t exist Check if multiple files exist How DiskInternals Linux Reader can help you ...