What is the main difference between the batch and at commands?

What is the main difference between the batch and at commands?
A . The batch command will run multiple times.The at command will only run once.
B . The batch command will run when system load is low. The at command runs at a specific time.
C . The at command reads commands from standard input. The batch command requires a command line argument.
D . The at command e-mails results to the user. The batch command logs results to syslog.

View Answer

Answer: B

Explanation:

The batch command is similar to the at command, except that it executes commands when the system load levels permit; in other words, when the load average drops below 1.5, or the value specified in the invocation of atd1. The at command allows us to schedule jobs using any of two commands: at and batch. While at runs commands at our specified time, batch runs commands when our system’s load average is below 0.82. Both commands read commands from standard input or a specified file, and both commands send the output of the commands to the user by mail1. Therefore, the main difference between them is the time of execution: at runs at a fixed time,

while batch runs when the system is idle.

Reference: 1: Linux At, Batch, Atq, Atrm Command Help and Examples – Computer Hope 2: The “at” Command in Linux | Baeldung on Linux