[Tutor] file io and the open() function

[Kirk Bailey]

A novice approaches the masters and asks:

I want to open a pair of files, read from one, wtite it to another,
appeding data.

The first is a list of local users, as:

me1
me2
him
him28
usfellas
him2
nothome
soandso

I want to append '@' and the text of a variable's contents, crating the
second file and filling it with:

me1@domain.foo
me2@domain.foo
him@domain.foo
him28@domain.foo
usfellas@domain.foo
him2@domain.foo
nothome@domain.foo
soandso@domain.foo

Which will be used as a mailing list to alert users of the system of
upcoming events. 

I wanted to craft this tool to use variables for the 2 files and the
domain name, so it would be a useful general purpose tool for use by
others. Alas, when it tries to open a file with a variable providing the
namer, it halts and catches fire, barfing evilgrams at me.


Also, as I cannot tell in advance howm any entries will be in the source
file, this thing has to work in a loop until the source file is
exausted, then close both files. How do I detet the endoffile and end
politely, instead of running off the end of the thing and tripping an
error?




-- 
Respectfully,
             -Kirk D Bailey (C)2001
              Addme! icq #27840081
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