join:tldr:6ab80
join: Produce a line for each unpairable line for file1.
$ join -a ${1} ${file1} ${file2}
try on your machine
The command "join" is used to combine two files based on a common field. Here is the breakdown of the given command:
- "join" is the command itself.
- "-a ${1}" is an option used to include all the non-matching lines from the ${1} file. The value of ${1} is a variable that should be provided when executing the command.
- ${file1} and ${file2} represent the two files to be joined.
So, when this command is executed, it will join the contents of ${file1} and ${file2} based on the common field, and include all the non-matching lines from the ${1} file. The joined output will be displayed in the terminal.
This explanation was created by an AI. In most cases those are correct. But please always be careful and
never run a command you are not sure if it is safe.