您能否尝试按照 GNU 中所示的示例进行编写和测试awk
。需要提及需要打印的所有行的地方lines_from
变量,那么有一个变量名为till_lines
它告诉我们需要从特定行打印多少行(例如-->从第一行打印接下来的 4 行)。另一方面,我已经测试了OP的代码,它对我来说工作得很好,它自调用以来使用 new_file 生成输出文件awk
在 bash 循环中并不是一个好的做法,因此在这里也将其添加为改进。
awk -v lines_from="1,2,3" -v till_lines="4" '
BEGIN{
num=split(lines_from,arr,",")
for(i=1;i<=num;i++){ line[arr[i]] }
}
FNR==NR{
value[FNR]=$0
next
}
(FNR in line){
print value[FNR] > "output_file"
j=""
while(++j<=till_lines){ print value[FNR+j] > "output_file" }
}
' Input_file Input_file
当我看到内容时output_file
我可以看到以下内容:
cat output_file
1 99 tut
2 24 bcc
3 32 los
4 33 rts
5 642 pac
2 24 bcc
3 32 los
4 33 rts
5 642 pac
6 23 caas
3 32 los
4 33 rts
5 642 pac
6 23 caas
7 231 cdos
解释:对上述内容添加详细解释。
awk -v lines_from="1,2,3" -v till_lines="4" ' ##Starting awk program from here and creating 2 variables lines_from and till_lines here, where lines_from will have all line numbers which one wants to print from. till_lines is the value till lines one has to print.
BEGIN{ ##Starting BEGIN section of this program from here.
num=split(lines_from,arr,",") ##Splitting lines_from into arr with delimiter of , here.
for(i=1;i<=num;i++){ ##Running a for loop from i=1 to till value of num here.
line[arr[i]] ##Creating array line with index of value of array arr with index of i here.
}
}
FNR==NR{ ##Checking condition FNR==NR which will be TRUE when 1st time Input_file is being read.
value[FNR]=$0 ##Creating value with index as FNR and its value is current line.
next ##next will skip all further statements from here.
}
(FNR in line){ ##Checking condition if current line number is coming in array then do following.
print value[FNR] > "output_file" ##Printing value with index of FNR into output_file
j="" ##Nullifying value of j here.
while(++j<=till_lines){ ##Running while loop from j=1 to till value of till_lines here.
print value[FNR+j] > "output_file" ##Printing value of array value with index of FNR+j and print output into output_file
}
}
' Input_file Input_file ##Mentioning Input_file names here.