[SOLVED] How to get output to be added into a file instead of replacing the file

ISStaras · 09-14-2012, 01:26 PM

So i'm running this command;

Code:

grep -f match.dat config > test.txt

and lets say I have another config file, say called config2... so now I've created a .sh file that looks like this

Code:

grep -f match.dat config > test.txt
grep -f match.dat config2 > test.txt

but the ">" character makes output of the 2nd line replace the output of the first instead of just adding to the file.. I would also like there to be a separator between the 2 outputs so I can clearly see where first ends and second starts.. lets say the output looks like this:

Code:

environment=${devel:env}
devel.ldapConfig.url=ldap\://155.165.192.12\:389
devel.ldapPool.timeBetweenEvictionRunsMillis=1234556
devel.ldapPool.initialPoolSize=2
devel.ldapPool.maxActiveConnections=2

and would like the test.txt file to look like this after both outputs are added:

Code:

-sh-3.2$ cat test.txt
config
environment=${devel:env}
devel.ldapConfig.url=ldap\://155.165.192.12\:389
devel.ldapPool.timeBetweenEvictionRunsMillis=1234556
devel.ldapPool.initialPoolSize=2
devel.ldapPool.maxActiveConnections=2

config2
environment=${devel:env}
devel.ldapConfig.url=ldap\://155.165.192.13\:389
devel.ldapPool.timeBetweenEvictionRunsMillis=777
devel.ldapPool.initialPoolSize=5
devel.ldapPool.maxActiveConnections=5

I'm definitely a newbie so any help would be appreciated, thanks!

TobiSGD · 09-14-2012, 01:29 PM

If you don't want the text to be replaced you have to use >> instead of >, so that your script looks like this

Code:

echo "config" > test.txt
grep -f match.dat config >> test.txt
echo "\nconfig2" >> test.txt
grep -f match.dat config2 >> test.txt

ISStaras · 09-14-2012, 01:35 PM

Quote:

Originally Posted by TobiSGD

If you don't want the text to be replaced you have to use >> instead of >, so that your script looks like this

Code:

echo "config" > test.txt
grep -f match.dat config >> test.txt
echo "\nconfig2" >> test.txt
grep -f match.dat config2 >> test.txt

How can I insert a line break between the two? Also, what's the \n for?

TobiSGD · 09-14-2012, 01:36 PM

the \n is the linebreak.

ISStaras · 09-14-2012, 01:42 PM

Quote:

Originally Posted by TobiSGD

the \n is the linebreak.

I see, not sure what i'm doing wrong but this is what i'm getting:

Code:

-sh-3.2$ cat report.sh
echo "config" > test.txt
grep -f match.dat config >> test.txt
echo "\nconfig2" >> test.txt
grep -f match.dat config2 >> test.txt
-sh-3.2$
-sh-3.2$ ./report.sh
-sh-3.2$ cat test.txt
config
environment=${devel:env}
devel.ldapConfig.url=ldap\://155.165.192.12\:389
devel.ldapPool.timeBetweenEvictionRunsMillis=1234556
devel.ldapPool.initialPoolSize=2
devel.ldapPool.maxActiveConnections=2
\nconfig2
environment=${devel:env}
devel.ldapConfig.url=ldap\://155.165.192.32\:389
devel.ldapPool.timeBetweenEvictionRunsMillis=3334556
devel.ldapPool.initialPoolSize=5
devel.ldapPool.maxActiveConnections=5

TobiSGD · 09-14-2012, 01:48 PM

Sorry, my error. If you want that echo can use the backslash characters, like \n, it has to be started with the -e option. Change that line to

Code:

echo -e "\nconfig2" >> test.txt

ISStaras · 09-14-2012, 01:52 PM

Quote:

Originally Posted by TobiSGD

Sorry, my error. If you want that echo can use the backslash characters, like \n, it has to be started with the -e option. Change that line to

Code:

echo -e "\nconfig2" >> test.txt

Awesome! thanks TobiSGD!

David the H. · 09-16-2012, 06:56 AM

I suggest that it's more readable just to use another separate echo.

Code:

echo "config" > test.txt
grep -f match.dat config >> test.txt
echo >> test.txt
echo "config2" >> test.txt
grep -f match.dat config2 >> test.txt

It's also better because there are NO standardized options in echo. POSIX doesn't specify any, so each shell has its own interpretation of them. When you need full portability, printf is the preferred choice.