我想将输出管道传输到bash中的多个文件

Question

I looked up how to do it but don't understand how to use tee . It is a little confusing because I am using an output from awk . Here is what I have so far: (keep in mind that I am a beginner)

num1=2
num2=4

awk 'if (/'$num1'/ == /'$num2'/) 
     {
         print "Hello"
     } 
     else  
     {
         print "Goodbye" 

     }' | tee file1.txt file2.txt

I don't know why the output from awk is not being printed in the text files.

Answer 1

Your awk command has syntax errors. @anubhava has given you a fix for that.

To demonstrate tee , let's do something simpler:

$ date | tee file1.txt file2.txt
Thu Jun 12 10:44:26 EDT 2014
$ cat file1.txt
Thu Jun 12 10:44:26 EDT 2014
$ cat file2.txt
Thu Jun 12 10:44:26 EDT 2014

To conclude: your invocation of tee is fine. Your output files do not contain any text because your awk program is only printing it's error messages to stderr and nothing to stdout. If you want all of awk's output to go into the files, redirect awk's stderr to stdout:

awk '...' 2>&1 | tee ...

I'll leave that explanation as an exercise

Answer 2

Use awk -v name=value option to pass shell variables to awk:

num1=2
num2=4
awk -v n1=$num1 -v n2=$num2 'BEGIN {if (n1 == n2) print "hello"; else print "Goodbye"}' 
 | tee file1.txt

To redirect output from awk itself:

awk -v n1=$num1 -v n2=$num2 'BEGIN {
    if (n1 == n2) print "hello"; else print "Goodbye"}' > output.txt

Answer 3

Piping output to tee will write the output to the file you indicate and write the output to stdout. Thus, if you want to write the output to multiple files, you can just pipe to another tee like so:

bbbco $ echo "hello world" | tee /tmp/helloworld1.txt | tee /tmp/helloworld2.txt
hello world

bbbco $ cat /tmp/helloworld1.txt 
hello world

bbbco $ cat /tmp/helloworld2.txt 
hello world