linux - 每 10 秒将 bash 输出重定向到新文件

Question

我有一个 COM_port，我是这样听的:

nc -l -p 1234.

因此，我想将输出重定向到一个文件，每 10 秒重定向到一个新文件。我知道如何将流程重定向到文件:

nc -l -p 1234 > file.txt

但是如何每 10 秒将流程写入新文件？ (前 10 秒为 file_10.txt，第二个为 file_20.txt，依此类推)。我害怕丢失流中的数据。这怎么可能？

谢谢。

Answer 1

#!/usr/bin/env bash
#              ^^^^- IMPORTANT! bash, not /bin/sh; must also not run with "sh scriptname".

file="file_$((SECONDS / 10))0.txt"        # calculate our initial filename
exec 3>"$file"                            # and open that first file

exec 4< <(nc -l -p 1234)                  # also open a stream coming from nc on FD #4

while IFS= read -r line <&4; do           # as long as there's content to read from nc...
  new_file="file_$((SECONDS / 10))0.txt"  # calculate the filename for the current time
  if [[ $new_file != "$file" ]]; then     # if it's different from our active output file
    exec 3>$new_file                      #   then open the new file...
    file=$new_file                        #   and update the variable.
  fi
  printf '%s\n' "$line" >&3               # write our line to whichever file is open on FD3
done