You're working much too hard :) 

#! perl -w
use strict;

while( <DATA> ) {
    s!([%&_~{}^#\\])!\\$1!g;
    print;
}

__DATA__
"% & _ ~ { } ^ # \ "
"Sonntag, 26.05.2013 - 13:13:27","0","Lieber Herr % , & text text with
+ some %special characters"
"Sonntag, 26.05.2013 - 13:35:47","1","Sehr gerne! ^ _~}# and here some
+ other characters"
"Sonntag, 26.05.2013 - 13:49:15","0",":-))"
"Mittwoch, 05.06.2013 - 18:12:09","0","Besten Dank, & hat prima geklap
+pt. {Greetings!}"
"Mittwoch, 05.06.2013 - 19:16:47","1","% _ text text!"
"Mittwoch, 05.06.2013 - 19:17:30","0","~Prima! #Danke!!"
"Samstag, 08.06.2013 - 09:21:09","1","_ 10. Jul Text text %"
"Samstag, 08.06.2013 - 10:08:45","0","Ja, osaka ffm lh 741 & ffm muc l
+h 114 abflug 16:00"

[download]
C:\test>junk
"\% \& \_ \~ \{ \} \^ \# \\ "
"Sonntag, 26.05.2013 - 13:13:27","0","Lieber Herr \% , \& text text wi
+th some \%special characters"
"Sonntag, 26.05.2013 - 13:35:47","1","Sehr gerne! \^ \_\~\}\# and here
+ some other characters"
"Sonntag, 26.05.2013 - 13:49:15","0",":-))"
"Mittwoch, 05.06.2013 - 18:12:09","0","Besten Dank, \& hat prima gekla
+ppt. \{Greetings!\}"
"Mittwoch, 05.06.2013 - 19:16:47","1","\% \_ text text!"
"Mittwoch, 05.06.2013 - 19:17:30","0","\~Prima! \#Danke!!"
"Samstag, 08.06.2013 - 09:21:09","1","\_ 10. Jul Text text \%"
"Samstag, 08.06.2013 - 10:08:45","0","Ja, osaka ffm lh 741 \& ffm muc 
+lh 114 abflug 16:00"

[download]
With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re: Escape special characters for a LaTeX file by BrowserUk
in thread Escape special characters for a LaTeX file by marek1703

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