file read and write - line by line
Input / Output example from a Well House Consultants training course
More on Input / Output [link]
Source code: flapper Module: U110
This program opens a file and reads and writes
it line by line
-- Open a file for read an test that it worked
fh,err = io.open("requests.xyz")
if err then print("OOps"); return; end
-- Open a file for write
fho,err = io.open("requests.new","w")
-- line by line
while true do
line = fh:read()
if line == nil then break end
if string.find(line,"Python") then
-- Following are good form
-- removes any file called test.bak
print (os.remove("test.bak") and "File removed" or "No action")
--[[ ---------- Sample Output -------------------------------
[trainee@easterton u110]$ lua flapper
antonia Perl XML PHP Tcl/Tk MySQL
barbara Tcl/Tk ASP Ruby Java
cherry Perl Java Ruby MySQL
delia XML PHP Java ASP
ethel MySQL Perl Tcl/Tk ASP
florence Ruby PHP Java ASP
gloria XML Perl Tcl/Tk MySQL
hazel PHP Python Perl Ruby ASP
iris Perl MySQL Java Tcl/Tk
jenny XML Perl Ruby ASP
kerry Perl Tcl/Tk Ruby MySQL
leane PHP Python ASP Perl Java
margaret XML Perl Ruby MySQL Tcl/Tk
nina Tcl/Tk Perl ASP Ruby
olivia MySQL Python ASP PHP
petra XML Tcl/Tk ASP Perl Ruby
queenie Ruby Perl ASP MySQL
rita PHP ASP Ruby Perl
sally Tcl/Tk Perl XML MySQL
tina Tcl/Tk Ruby Java
uva MySQL Perl Java PHP
venus Java Perl Ruby ASP
wendy Perl Tcl/Tk ASP MySQL
xena Java Perl PHP ASP XML
yollanda Ruby MySQL Tcl/Tk
zoe Ruby ASP Perl PHP
adam Tcl/Tk Perl Python MySQL
barry Python XML Java Perl PHP
charles Perl Ruby MySQL Tcl/Tk
david Perl Tcl/Tk Java
ed Ruby Perl Java PHP
fred MySQL Perl Java XML
graham Java Perl Tcl/Tk
harry PHP Python Java
ivan Ruby Java Perl Tcl/Tk MySQL
john PHP XML Java Perl
ken Tcl/Tk Python Java Perl
len Perl Java MySQL Ruby
morris Perl Java PHP Tcl/Tk
nigel PHP Python Java Perl
orpheus MySQL Ruby Tcl/Tk XML
peter PHP Java Perl
quentin Tcl/Tk Perl PHP Ruby
rupert Java Python MySQL
steve Tcl/Tk Perl PHP Ruby
tommy Perl Java XML
ulsyees Java PHP Perl
victor Ruby Perl Tcl/Tk MySQL
william Ruby Perl PHP
xavier PHP Java Perl
yuri XML PHP Perl Tcl/Tk
zachary MySQL Java Tcl/Tk
Learn about this subject
This module and example are covered on the following public courses:
* Learning to program in Lua
* Lua Programming
* Lua Programming
Also available on on site courses for larger groups
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Yes. We have over 700 books in our library. Books covering Lua are listed here and when you've selected a relevant book we'll link you on to Amazon to order.
This example comes from our "Input / Output" training module. You'll find a description of the topic and some other closely related examples on the "Input / Output" module index page.
Full description of the source code
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