NetNews Offline 2/NetNews Offline Volume 2.iso/news/comp/lang/c-part2/10929

Internet Message Format | 1996-08-05 | 1.8 KB

Path: mail2news.demon.co.uk!genesis.demon.co.uk
From: Lawrence Kirby <[e-mail]>
Newsgroups: comp.lang.c
Subject: Re: Input filename for fopen()?
Date: Wed, 20 Mar 96 17:43:44 GMT
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Message-ID: <[e-mail]>
References: <4iikju$[e-mail]>
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In article <4iikju$[e-mail]>
           [e-mail] "XY Xie" writes:

>How do I get the user to input filename for fopen()  ?
>
> I tried a gets(filename) before a fopen(filename,"r"). It worked for
>files in the current dir (when the user only has to enter the
>filename) , but  it does not work for files in other dirs (when the
>user has to enter something like "c:\\windows\\letter.txt").

Did you try having the user enter:

  c:\windows\letter.txt

or

  c:/windows/letter.txt  ?

>When I tried to type the filename directly into fopen(), it worked
>fine for any file any where.
>So I guess the problem lies in the ' \ '  because C treats it as an
>escape sequence. How do I get around this?

\ is an 'escape' characters in string literals in C source but that doesn't
imply it has any special significance on file input/output. So unless your
OS treats it specially you enter \ for \ and not \\ at runtime.

Also gets() is dangerous and should never be used because you can't prevent
it writing beyond the buffer you give it. Use fgets() instead but be sure
you remove any trailing '\n' character before passing the string to fopen().

--
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Lawrence Kirby | [e-mail]
Wilts, England | [e-mail]
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