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如何知道awk命令是否在不破坏原始输出的情况下打印了某些内容

awk gawk bash

Saeed isa · 技术社区 · 8 年前

我正在尝试使用AWK命令,它为我打印得非常好,我想要什么样的确切方式

我使用的命令: gawk 'BEGIN{RS=ORS="\n\n" {s=tolower($0)} s~/word1|word2/' input_file.log

我试过:

status=gawk 'BEGIN{RS=ORS="\n\n" {s=tolower($0)} s~/word1|word2/' input_file.log

if [ -z $status]
then
    //status is empty or null, means nothing printed in awk command
    echo "nothing"
else
    //printed something in awk command
    echo $status

echo $status 按顺序打印所有行,行之间没有“新行”

如何在不损坏awk的情况下打印原始打印?

输入文件:

line 0 no words in here

line 1 starting
line 1 word1

line 2 no words here as well

line 3 starting
line 3 word2
line 3 end

line 4 nothing
line 5 nothing

line 1 starting
line 1 word1

line 3 starting
line 3 word2
line 3 end

stat=$(gawk 'BEGIN{RS=ORS="\n\n" {s=tolower($0)} s~/word1|word2/' input_file.log) echo $stat

我得到输出:

line 1 starting line 1 word1 line 3 starting line 3 word2 line 3 end

提前感谢!

2 回复 | 直到 8 年前

RavinderSingh13 Nikita Bakshi 8 年前

不完全确定,因为您没有显示任何示例Input_文件或预期输出,所以请尝试使用 echo "$status" .

编辑:

status=$(awk 'BEGIN{RS=ORS="\n\n"} {s=tolower($0)} s~/word1|word2/' Input_file)
if [[ -z $status ]]
then
    echo "nothing"
else
    echo "$status"
fi

Akshay Hegde 8 年前

exit awk 是否打印了内容

更正代码

从…起

gawk 'BEGIN{RS=ORS="\n\n" {s=tolower($0)} s~/word1|word2/' input_file.log

status=$(gawk 'BEGIN{RS=ORS="\n\n"}tolower($0)~/word1|word2/' input_file.log)

echo "$status"

这是因为 当您引用参数时(是否 echo , test 或其他命令),则它,shell执行其正常的魔法,寻找空白来确定每个参数的开始和结束位置。

更正现有代码

#!/usr/bin/env bash

status=$(gawk 'BEGIN{RS=ORS="\n\n"}tolower($0)~/word1|word2/' input_file.log)
if [  -z "$status" ]; then
       echo "looks like nothing matched and so nothing printed"
else
       echo "awk matched regex and printed something"
fi

以下是用于检查awk是否打印了内容或未使用退出代码的代码:

gawk 'BEGIN{RS=ORS="\n\n"}f=(tolower($0)~/word1|word2/){e=1}f; END{exit !e}' input_file.log

# check exit code 
if [ "$?" -eq 0 ]; then
       echo "awk matched regex and printed something"
else
       echo "looks like nothing matched and so nothing printed"
fi

$ cat test.sh 
#!/usr/bin/env bash

gawk 'BEGIN{RS=ORS="\n\n"}f=(tolower($0)~/word1|word2/){e=1}f; END{exit !e}' "$1"
if [ "$?" -eq 0 ]; then
       echo "awk matched regex and printed something"
else
       echo "looks like nothing matched and so nothing printed"
fi

用于测试的示例文件

$ echo 'word1' >file1

$ echo 'nothing' >file2

文件的内容

$ cat file1
word1

$ cat file2
nothing

使用第一个文件执行

$ bash test.sh file1
word1

awk matched regex and printed something

$ bash test.sh file2
looks like nothing matched and so nothing printed