bash - BASH - GREP - 反转很多不起作用

Question

我试图通过用户“apache”找到一些打开的文件描述符。我想排除ls: /proc/PID/fd: No such file or directory但 GREP 排除不起作用：

# for pid in $(lsof -u apache | awk '{ print $2 }' | uniq); do ls -1 /proc/$pid/fd | grep -v "No"; done | wc -l 
ls: /proc/PID/fd: No such file or directory
1944

Answer 1

尝试|& grep -v "No such file or directory"

不像|,|&也会重定向错误输出ls

Answer 2

尝试：

for pid in $(lsof -u apache | tail -n +2 | awk '{ print $2 }' | uniq); do ls -1 /proc/$pid/fd ; done | wc -l