I am trying to write a sed command to do the following.

I have a line in my file, something like this

*.info;mail.none;authpriv.none;cron.none  /var/log/messages

This has to be replaced with,

*.info;mail.none;authpriv.none;cron.none;local2.none;local5.none    /var/log/messages

Conditions

1. There is no fixed spacing between cron.none and /var/log/messages, the spacing might vary from file to file. original *.info;mail.none;authpriv.none;cron.none /var/log/messages desired *.info;mail.none;authpriv.none;cron.none;local2.none;local5.none /var/log/messages

or

original

*.info;mail.none;authpriv.none;cron.none            /var/log/messages
desired
*.info;mail.none;authpriv.none;cron.none;local2.none;local5.none          /var/log/messages

just append ;local2.none;local5.none

2. Sometime the file might have already ;local2.none;local5.none, in this case ignore the append. ex

*.info;mail.none;authpriv.none;cron.none;local2.none;local5.none    /var/log/messages
*.info;mail.none;authpriv.none;cron.none;local2.none;local5.none    /var/log/messages

3. sometimes the file might have local6.none, but no local2.none;local5.none, in this case append ;local2.none;local5 ex

*.info;mail.none;authpriv.none;cron.none;local6.none    /var/log/messages
*.info;mail.none;authpriv.none;cron.none;local2.none;local5.none;local6.none    /var/log/messages

Below are the few things I tried.

1)

sed -i -e "/*.info;mail.none;authpriv.none;cron.none;local2.none;local5.none.*\ \/var\/log\/messages/! /*.info;mail.none;authpriv.none;cron.none.*\ \/var\/log\/messages/ s/cron.none/cron.none;local2.none;local5.none/g" $SYSLOGCONFFILE

sed -i -e "/*.info;mail.none;authpriv.none;cron.none.*\ \/var\/log\/messages/.*local2.none;local5.none.*/!s/cron.none/cron.none;local2.none;local5.none/g" $SYSLOGCONFFILE

sed -i -e "/*.info;mail.none;authpriv.none;cron.none;local2.none;local5.none.*\ \/var\/log\/messages/! /*.info;mail.none;authpriv.none;cron.none.*\ \/var\/log\/messages/ s/cron.none/cron.none;local2.none;local5.none/g" $SYSLOGCONFFILE

nothing seems working. TIA

CodePudding user response：

awk is a better tool for accomplishing what you are trying to do, in this case:

#!/bin/sh

awk -v inject=";local2.none;local5.none" -v postfix=";local6.none" '{
    exist=index( $1, inject ) ;
    other=index( $1, postfix ) ;
    print "\n\texist=", exist ;
    print "\n\tother=", other ;
    if( exist > 0 ){
        print "\n *1*"
        print $0 ;
    }else{
        print "\n *2*"
        if( other > 0 ){
            beg=substr( $1, 1, other-1 ) ;
            end=substr( $1, other ) ;
            printf("%s%s%s %s\n", beg, inject, end, $2 ) ;
        }else{
            printf("%s%s %s\n", $1, inject, $2 ) ;
        } ;
    } ;
}'

CodePudding user response：

Using sed

$ sed -i.bak '/cron.none.*local2.none;local5.none/!{s/cron.none/&;local2.none;local5.none/}' input_filr
*.info;mail.none;authpriv.none;cron.none;local2.none;local5.none            /var/log/messages
*.info;mail.none;authpriv.none;cron.none;local2.none;local5.none    /var/log/messages
*.info;mail.none;authpriv.none;cron.none;local2.none;local5.none;local6.none    /var/log/messages
*.info;mail.none;authpriv.none;cron.none;local2.none;local5.none  /var/log/messages