francois@baal:~$ cat > 1
wireshark:x:128:toto
francois@baal:~$ cat > 2
test1
test2
test3
francois@baal:~$ cp 1 1.old ; sed '/wireshark/ s/$/,'$(cat 2 | tr '\n' ',')'/;s/,$//' 1.old > 1 francois@baal:~$ cat 1
wireshark:x:128:toto,test1,test2,test3
francois@baal:~$ rm 1 1.old 2
francois@baal:~$ |