[Question] program edit file

I want to make auto add programs to my OS, how I make a program to edit another program or file?
Thanks for the help!

Try the filesystem API, specifically fs.open()

my_hat_stinks, on 06 June 2012 - 10:48 AM said:

Try the filesystem API, specifically fs.open()

Can you show me an example?

The linked documentation on the seems pretty clear. What are you having trouble with?

kazagistar, on 06 June 2012 - 05:31 PM said:

The linked documentation on the seems pretty clear. What are you having trouble with?

I need to make login system with more than 1 user, i need the login program to edit the users file and add more users into it.

Use f.readLine and f.writeLine along with tables, the latter which are in the lua reference document.

OmegaVest, on 06 June 2012 - 08:01 PM said:

Use f.readLine and f.writeLine along with tables, the latter which are in the lua reference document.

you can give me an exaple plz?

If you really want an example, here is one:

filename = 'users'
userfile = fs.open(filename, 'a')	-- 'a' stands for append mode, you also have 'w' (write) and 'r' (read)
while true do
  line = userfile.readLine()	  -- read a line to the variable 'line'
  if not line then		-- there are no more lines
	break
  end
  print(line)		  -- print the line you just read
end
userfile.writeLine('new user')	-- append a line to the file
userfile.close()		  -- close the file (or could you've guessed it? :)/>/>)

Note: code is untested

But really, a word of advice, you can do yourself a huge favor by learning Lua from the absolute beginning (statements, functions, conditionals, loops, …).
Maybe you understand these all ready, but when you learn further from there one, you automatically gain the knowledge and insight to understand the documentation on the wiki or from other sources.
It might seem like a waste of time, and you want to get going, but it really is a must to write decent programs.

Orwell, on 07 June 2012 - 01:17 PM said:

If you really want an example, here is one:

filename = 'users'
userfile = fs.open(filename, 'a')	-- 'a' stands for append mode, you also have 'w' (write) and 'r' (read)
while true do
  line = userfile.readLine()	  -- read a line to the variable 'line'
  if not line then		-- there are no more lines
	break
  end
  print(line)		  -- print the line you just read
end
userfile.writeLine('new user')	-- append a line to the file
userfile.close()		  -- close the file (or could you've guessed it? :)/>/>)

Note: code is untested

But really, a word of advice, you can do yourself a huge favor by learning Lua from the absolute beginning (statements, functions, conditionals, loops, …).
Maybe you understand these all ready, but when you learn further from there one, you automatically gain the knowledge and insight to understand the documentation on the wiki or from other sources.
It might seem like a waste of time, and you want to get going, but it really is a must to write decent programs.

Thank you!!!
Done login system!

Orwell, on 07 June 2012 - 01:17 PM said:

If you really want an example, here is one:

filename = 'users'
userfile = fs.open(filename, 'a')	-- 'a' stands for append mode, you also have 'w' (write) and 'r' (read)
while true do
  line = userfile.readLine()	  -- read a line to the variable 'line'
  if not line then		-- there are no more lines
	break
  end
  print(line)		  -- print the line you just read
end
userfile.writeLine('new user')	-- append a line to the file
userfile.close()		  -- close the file (or could you've guessed it? :(/>/>)

Note: code is untested

But really, a word of advice, you can do yourself a huge favor by learning Lua from the absolute beginning (statements, functions, conditionals, loops, …).
Maybe you understand these all ready, but when you learn further from there one, you automatically gain the knowledge and insight to understand the documentation on the wiki or from other sources.
It might seem like a waste of time, and you want to get going, but it really is a must to write decent programs.

that won't work at all for me..

That's because append mode won't give you read methods.

what is append mode?

Append mode keeps what has been written and then you edit…

When opening a file with the FS API, specifying the "a" mode will cause all file writes to appear at the end of the file, after the existing contents (they are "appended"). Normal write mode overwrites the existing file.