Question

我需要知道是否可以标记bash脚本行号，然后在保存的行号处重新启动该脚本。

代码：

#!/bin/bash
while read -r line; do #I'm reading from a big wordlist
command1 using $line
command2 using $line
done

具体来说，有没有办法将脚本的当前$行号自动写入单独的文本文件中，以便脚本从指定的行号开始，这样我就不必从头开始一切如果我不得不停止脚本？

有意义吗？

非常感谢！

Answer 1

这可能有所帮助：

#!/bin/bash

TMP_FILE="/tmp/currentLineNumber"                         # a constant

current_line_count=0                                      # track the current line number

processed_lines_count=0

# Verify if we have already processed some stuff.
if [ -r "${TMP_FILE}" ]; then
  processed_lines_count=$(cat ${TMP_FILE})
fi

while read -r line; do                                    # I 'm reading from a big wordlist

    # Skip processing till we reach the line that needs to be processed.

    if [ $current_line_count -le $processed_line_count ]; then

      # do nothing as this line has already been processed
      current_line_count=$((current_line_count+1))        # increment the counter
      continue

    fi

    current_line_count=$((current_line_count+1))
    echo $current_line_count > ${TMP_FILE}                # cache the line number

    # perform your operations
    command1 using $line
    command2 using $line

done

Answer 2

这应该有效：

    #!/bin/bash
    I=`cat lastline`;
    A=0;

    while read -r line; do
           if [$A>=$I]; then
               command1 using $line
               command2 using $line
               (( I++ ))
               echo "$I" > "lastline";
           fi;
           (( A++ ))
    done

如果要重新启动，请记住必须删除lastline。： - ）

Answer 3

仅限bash的解决方案很不错，但您可以通过使用其他工具简化重新启动来获得更好的性能。与您问题中的脚本一样，以下内容采用stdin上的wordlist。

#!/bin/sh

# Get the current position, or 0 if we haven't run before
if [ -f /tmp/processed ]; then
  read processed < /tmp/processed
else
  processed=0
fi

# Skip up to the current position
awk -v processed="$processed" 'NR > processed' | while read -r line; do

  # Run your commands
  command1 using $line
  command2 using $line

  # Record our new position
  processed=$((processed + 1))
  echo $processed > /tmp/processed

done

哦，我写这个的方式，它与Bourne shell兼容，所以它不需要bash。

是否可以标记并保存特定的bash脚本行号并在该保存的位置重新启动脚本？

3 个答案: