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From: clark@umn-cs.CS.UMN.EDU (Robert P. Clark)
Newsgroups: comp.lang.c
Subject: RE: strange C
Message-ID: <12726@umn-cs.CS.UMN.EDU>
Date: 10 May 89 14:10:23 GMT
Organization: University of Minnesota, Minneapolis
Lines: 36

in article 19474 bvickers writes:

: I've come across a very strange problem in one of my programs.  I'll
: list the function that's causing the problems and then discuss what
: those problems are.
: 
: Globals:  struct msg_node *first_msg, *last_msg;
: 
: void output_msgs()
: {
... deleted
:     printf("%s\n",current->string);
:     printf("&");
... deleted
: }
: 
: Now, this function is supposed to output all the messages that are on
: the linked list from first to last.  But something strange happens.
: After the function has output its last message, it fails to continue
: on to the next line (printf("&")).  The ampersand isn't output until
: the next call to output_msgs().  
: 
: Why is this happening?   All help appreciated.
: 

I believe that the program is working correctly, there really is
no problem.  The "&" is not printed until later, because output is
buffered.  Printing a "\n" - as in printf("%s\n",current->string);
flushes the output buffer.  The next call to printf("&"); is 
executed, but the buffer is not flushed until later.  You can
force the "&" to be printed by manually flushing the output buffer
with a call to  fflush(stdout);  



                     Bob Clark        clark@umn-cs.cs.umn.edu