changing line in text file

tescik80 · 02-09-2006, 09:00 AM

hi
i am writting a script that needs to manipulate with configuration file, and i don't know how safely change a line in a file, i need to change few chars in that line, but i can also replace it.
so if you know how to do that [so other data in a file is not changed] please post here

some example would be usefull
thanks.

kshkid · 02-09-2006, 09:04 AM

is it acceptable that you can have the changes in conf.temp
and then rename conf.temp to conf

could you please post sample output, changes expected and the final output conf file

kshkid · 02-09-2006, 09:04 AM

is it acceptable that you can have the changes in conf.temp
and then rename conf.temp to conf

could you please post sample output, changes expected and the final output conf file

Matir · 02-09-2006, 09:07 AM

Try using 'sed' to perform the replacement you need:

Code:

sed 's/OLDTEXT/NEWTEXT/g'

tescik80 · 02-09-2006, 09:10 AM

unreadable color sorry

tescik80 · 02-09-2006, 09:10 AM

#####sample:
useSyslog 1
syslogFacility 0

# auto generation
timer period=3600 nextUpdateBuffer=300 start=00:00:00

other stuff here.....

##############################################################################

file is much bigger, but point is to change start parameter to different full hours.

possible output:

######sample:
useSyslog 1
syslogFacility 0

# auto generation
timer period=3600 nextUpdateBuffer=300 start=17:00:00

other stuff here.....

##############################################################################

it would be ok to rename file

tescik80 · 02-09-2006, 09:14 AM

Quote:

Originally Posted by Matir

Try using 'sed' to perform the replacement you need:

Code:

sed 's/OLDTEXT/NEWTEXT/g'

but how to pick the line i need to replace?
i need only 1 line to be changed, i am really newbie...

sirclif · 02-09-2006, 01:46 PM

if it's line 10:

sed '10 s/OLDTEXT/NEWTEXT/g'

tescik80 · 02-10-2006, 05:30 AM

thx a lot, i will test in in a moment

kshkid · 02-10-2006, 11:46 PM

Quote:

Originally Posted by sirclif

if it's line 10:

sed '10 s/OLDTEXT/NEWTEXT/g'

you cannot be sure which line needs to be modified,
instead of hard-coding search the pattern and then replace

Code:

sed '/OLDTEXT/ s/OLDTEXT/NEWTEXT/g' file

Matir · 02-12-2006, 09:25 AM

Quote:

Originally Posted by kshkid

you cannot be sure which line needs to be modified,
instead of hard-coding search the pattern and then replace

Code:

sed '/OLDTEXT/ s/OLDTEXT/NEWTEXT/g' file

You don't need both the search and substitute patterns, if they're identical.

tescik80 · 02-12-2006, 12:33 PM

can i change a specified fragment of line or just put a new line onstead old one?
that would help a lot, woudn't have to know what param is set.

Tinkster · 02-12-2006, 01:06 PM

Why don't you just run the suggested sed command against
your file and see what it does?

Cheers,
Tink

tescik80 · 02-20-2006, 05:43 AM

can i use maskwith sed?
if i can how would syntax look like?

lets say i awant to change :

i am noob ???????? [8 letters there, which i want to change and i dont know them]

sed s/start=????????/start=$czas/g file1 > file2

what to put there in ????????