Question

I have a command line like this:

awk  '$9 < 0.1' s_all_frq.txt | wc -l  
awk  '$9 >= 0.1 && $9 < 0.2 ' s_all_frq.txt | wc -l

when I run it I get an output like this.

$ awk  '$9 < 0.1' s_all_frq.txt | wc -l  
63278
$awk  '$9 >= 0.1 && $9 < 0.2 ' s_all_frq.txt | wc -l  
2346

when I try to save this in a text file it always replace the first output. so I use these commands:

awk  '$9 < 0.1' s_all_frq.txt | wc -l > 1.txt 

awk  '$9 >= 0.1 &&$9 < 0.2 ' s_all_frq.txt | wc -l > 1.txt

and I get only 2346 saved on the text file. which I assume that the file got overwritten. I wonder if it’s possible to add something to this command to save the output as new line in the file so I will have this in the final file:

63278
2346

Answer 1

Use >> instead of > to append instead of replace.

awk '$9 >= 0.1 &&$9 < 0.2 ' s_all_frq.txt | wc -l >> 1.txt

Other example:

user@home:~$ echo A >1.txt
user@home:~$ echo B >1.txt
user@home:~$ cat 1.txt
B
user@home:~$ echo C >>1.txt
user@home:~$ cat 1.txt
B
C
user@home:~$