Interpreting user input

I need to understand the user's input of "18小时前," which means "18 hours ago" in Chinese. They probably want to know the current time relative to that phrase. I could assume they're asking for a timestamp or doing some calculations. Since they didn't specify a question, I'll need to clarify if they want the exact timestamp 18 hours ago in their local timezone. I can use the date command to get both the current time and the time from 18 hours ago, though I need to consider the timezone factors.Computing timestamp request

I’m looking to compute the timestamp for "18 hours ago." I should ask for clarification: "Do you want the exact timestamp from now, and which timezone or format do you prefer?" But, I can keep it simple by assuming the local system timezone and offering a few common formats. I can run shell commands like date to get the current time and retrieve the relative timestamp. However, I don't know which OS the user is on, so I need to be mindful of that too.Running date commands for timestamp

I'm considering running the command date -u to detect the environment and support both Linux and macOS compatibility. I want to try GNU date first; if that fails, I’ll switch to BSD date formats. For ISO8601 formatting, I'll use date -Iseconds on GNU and a compatible format for macOS. I also need to address that the user's input is in Chinese, so I should respond in Chinese to keep things clear and concise. I'll prepare my commands to calculate "now" and "18 hours ago" for both local and UTC time.Setting up date commands

I need to provide both local time and UTC timestamps for "now" and "18 hours ago." First, I’ll set the working directory, defaulting to the local path. To get the times, I can use GNU and BSD date commands depending on what's available. For GNU date, I’ll run commands to get the current time and 18 hours ago in both local and UTC formats. The same goes for BSD date, but using its specific syntax. I’ll bundle everything into a single script to keep it organized!