I am very new to scripting in UNIX and in need of help. I am creating a program that will check a file that has a target time in the form of HH:MM:SS before another program can begin executing. The file with the target time will only have that target time in it and nothing else.

Is there any way to validate that the time that is entered in the file is entered correctly when using: date +%T as the command to check the current time? I would like to validate the target time in the file in the program that I am creating. Please help