如何忽略 ls 命令中没有这样的文件目录的错误？

Question

How to ignore the error No such file directory ?

ls /opt/data/config/run_*.config | cut -f1 -d '.' | cut -f2 -d '_' 2>/dev/null
ls: cannot access /opt/data/config/run_*.config: No such file or directory

Answer 1

You are doing the following:

ls <something> | cut <some_cut> | cut <some_other_cut> 2>/dev/null

This will do the ls , the first and the second cut , and when an error is generated at the second cut , it will be sent to the null device (which means it will be removed).

If you want to remove the error message from any command, you need to put it immediately after the corresponding command, so you get three cases:

Case 1: ls <something> | cut <some_cut> | cut <some_other_cut> 2>/dev/null
Case 2: ls <something> 2>/dev/null | cut <some_cut> | cut <some_other_cut>
Case 3: ls <something> 2>/dev/null | cut <some_cut> 2>/dev/null | cut <some_other_cut> 2>/dev/null

Case 1 is the situation you're having now.
Case 2 and 3 are possible solutions: case 2 only removes error messages from the ls command, while case 3 removes error messages from every command.