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Full Discussion: Pure C function pointer on printing vowels twice
Top Forums Programming Pure C function pointer on printing vowels twice Post 302997637 by yifangt on Wednesday 17th of May 2017 03:21:15 PM
Old 05-17-2017
Is there another layer hidden behind for printing with putchar() in the if-condition?
The return value is EOF or a single vowel, which is the first part bugging me.

Does that mean in if (putchar(c) == EOF || putchar(c) == EOF) , function putchar(c) gets actually executed twice?

I thought this line is just a condition, and before the end only the else block is executed so that the value is 'e', without printing.
Let me put my question in another way:
Is there another layer for printing hidden behind, such as when 'e' is encountered in 'Test'?
Code:
putchar(c);    //Is this the place 'e' get printed the first time?
left ~> (putchar(e) == EOF) is false, 0
putchar(c);    //Is this the place 'e' get printed the second time?
right ~> (putchar(e) == EOF is false, 0
so that, the if (0 || 0) condition still false; 
else block executed

Is this correct?
Thanks!
Last edited by yifangt; 05-17-2017 at 04:26 PM..
 

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       RFC 959, RFC 2228, RFC 2389 and RFC 2428.

Pure-FTPd team							      1.0.36								pure-pw(8)
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