writing

[Anon]

I'm baaaacccckkkkk! lol, I need help again. OK, I need to erase a single line in a file. All this is for a mail list(just so ya know) I need it to erase one e-mail address and the name with it! In the db (just a txt file) its stored as "Name|E-mail" now how can I delete one line without it wiping out the whole freggin file?!?

[Anon]

This is not tested, but sounds ok to me:

Read the file into an array using the file() function.
Go through the array and see where the offencing line is.
When found, use the array_splice() function (PHP4 according to the manual, but is available in PHP3 too) to remove that part of the array.
use the file functions to write the data back to a new temp file.
move the temp file over the original file.

Note: don't start overwriting your files immediately, always write a new file first. If PHP crashes during the file-write, no data is lost.

[Anon]

Could you explain how to do all this a little bit more? I'm kinda new at programming (either that or a slow learner).

[Anon]

OK, I am working with PHP 3. Once I find the line is there a way to tell the script to write erase that line? example:

$fcontents = file ('/usr9/home/elikag/log.txt');
while (list ($line_num, $line) = each ($fcontents)) {
if (ereg(".zip",$line,$regs)){
problem!
}
}

the script finds what I'm looking for but I have no clue how to tell it to erase it! (thats where the problem is)

[Anon]

Step 1: get and read the manual.
You don't have to spend years on it, just read the intro and look at a few code examples.

Now, move to the filesystem functions. Read about the file() functions and what it does.

Easy enough, $my_file=file("filename");

That gives you an array filled with the lines of text from your file.

We want to look at every element of the array we just made.
So, first we need to know how many elements there are in this array.

Move to the array_functions section of the manual, look at the count() function.

count($my_file)
tells us how many entries there are in this array.

Now we have the data, we know how much data we have, how do we get to the data?

In an array you can adres data like this: $my_file[$item_counter]

If I need the first element in the array:
$my_file[0];

then 5th:
$my_file[4];

Now how do I know which element is the one I want to delete?

Go to the control-structures and string_functions section.
Look up IF and SRTCMP

You can imagine it must look something like this:
if (strcmp($my_file,"this is the text I want to delete"))
{
delete the entry
};

Now we want to do this for every entry, go back to the control structures, look up the FOR statement.

for (condition)
{
do this
};

Now we have allmost everything we need:

for ($item_counter=0;$item_counter<count($my_file);$irem_counter++)
{
if (strcmp($my_file[$item_counter],"this is the line I want to delete"))
{
delete the entry
};
};

That should get you started, I'll leacve the most insteresting part (the array_splice()) for you to figure out.....

evil grin

[Anon]

That is a PHP4 function, I am using PHP3. Will it work.