I think stupok's way would be best.
Code:
new f = fopen("yourfile.txt", "rt");
new line;
new bool:delete;
new data[/* your data size */];
while( !feof(f) )
{
fgets(f, data, sizeof(data) - 1);
if( /* this is the line you want to delete */ )
{
delete = true;
break;
}
line++;
}
fclose(f);
if( delete )
write_file("yourfile.txt", "", line);
That will make the line blank, and shouldn't be a problem when you need to read data.
Just make a "if( !data[0] ) continue;" type check.
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