Semiconductor & Computer Engineering
- Variables
- File Handling
- Hash Tables
- Binary variables
- INI Files
- Text Files
Plain text files are files you can edit via a basic editor like notepad and has no special structure. Below are a few handy commands and identifiers to work with plain text files.
Contents
File Info
To determine if a file exists we can use the $isfile() identifier.
$isfile(file.txt)
In many cases you'd want to check the number of lines in the file. $lines() will help you there.
$lines(file.txt)
Reading From a Text File
The $read() identifier is a very powerful command that can be used to read from a text file in a variety of ways.
n Switch
By default, $read will evaluate the text it reads as if it was mSL code. To prevent this behavior you must use the n switch. Throughout this article we will ALWAYS use that switch. Improper use of the $read() identifier without the 'n' switch could leave your script highly vulnerable.
Reading a Random Line
The most basic functionality $read() offers is the ability to read a random line from a particular file. The syntax is:
; read a random line from file.txt $read(file.txt, n)
Reading a Specific Line
To read a specific line from a file you can specify the line number as the third argument.
$read(file.txt, n, line)
Searching the File
$read() offers three methods for searching a file:
- Scanner
- Wildcard Pattern
- Regular Expression Pattern
Scanner
The scanner is the most primitive search of the three. It will go through each line comparing the pattern provided to the first part of the line. If a match is found, mIRC will return the text that followed the pattern.
Consider the following abbr.txt:
lol laughing out loud lmao Laughing my ass off btw by the way brb be right back
We can use the following alias to get the abbreviation we are looking for.
alias abbr return $read(abbr.txt, ns, $1)
Executing the following code:
//echo -a $abbr(lol) //echo -a $abbr(brb)
Will produce the following output:
laughing out loud be right back
Wildcard And RegEx Patterns
Both the wildcard pattern matching and the regex pattern matching works by searching for the first matching line and returning the entire line. It follows the same syntax as the scanner:
; A wildcard pattern match: $read(file.txt, nw, *wildmatch*) ; A regex pattern match: $read(file.txt, nr, /pattern/)
Starting Line
If you specify a line number after the pattern, that line will be used as the first line to start searching from.
For Example:
; Start searching from line 400: $read(file.txt, nw, *hello*, 400)
Iterating Over Matches
$readn is an identifier that returns the line that $read() matched. We can use that to start searching for our pattern on the next line.
For example, to search all the line containing the word 'test' in a file, we can construct a loop like this:
//while ($read(file.txt, nw, *test*, $calc($readn + 1))) echo -a $v1
In the code above, $readn starts at 0. We use $calc() to start at line 1. Every match $read() will start searching on the next line. When no more matches are after the line specified $read will return $null - terminating the loop.
Writing to a Plain Text File
The /write command can be used to manipulate a text file in a variety of ways.
Appending a Line
/write's simplest operation is the append operation. By default, /write will write a text line to the end of the file.
/write text.txt <string>
Inserting a Line
To insert text at specific line we have the following syntax:
/write -il<line> file.txt <text>
For example, the following line will write "Hello There!" at line 2.
/write -il2 file.txt Hello There!
Deleting a Line
The /write command provides the ability to delete a specific line from a file.
; Delete line <line> from a file: /write -dl<line> file.txt
Clearing A File
The -c switch on /write can be combined to clear the file before writing to it.
; clear the file /write -c file.txt
Deleting a File
The delete a file, you can use the /remove command:
/remove file.txt ; send to the recycle bin /remove -b file.txt