Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ames!amdahl!kevin
From: kevin@uts.amdahl.com (Kevin Clague)
Newsgroups: comp.sys.amiga
Subject: Re: Struggling through the "C"
Message-ID: <13.6va2CVf1010TxC9.@amdahl.uts.amdahl.com>
Date: 1 Apr 89 12:21:57 GMT
References: <12000@louie.udel.EDU> <97113@sun.Eng.Sun.COM>
Reply-To: kevin@amdahl.uts.amdahl.com (Kevin Clague)
Organization: Amdahl Corporation,  Sunnyvale, CA 94086
Lines: 73

In article <97113@sun.Eng.Sun.COM> cmcmanis@sun.UUCP (Chuck McManis) writes:
>In article <12000@louie.udel.EDU> (Rob Lizak Jr.) writes:
>> FOR I=1 TO LEN(A$)
>>   PRINT MID$(A$,I,1);
>> NEXT I
>
>C equivalent might be more syntactically written as 
>	for (i=0; i < strlen(a); i++) 
>		printf("%c", a[i]);
>	
>Get a copy of the book "Programming in C" by Stephen G. Kochan, ISBN
>0-8104-6261-3, it has a good discussion of strings.
>
>>no matter what I put for the declaration... it wouldnt work!  I added this
>>to the program to try to make it work... whats wrong with this?
>
>char	*a; /* This is a pointer to a string */
>char	a[80]; /* this is a pointer to a string with 80 bytes allocated */
>
>Outside of a function you can declare :
>char	*a = "this is a test string."; /* the auto allocates space */
>-or-
>char	a[80];	/* Global variable */
>main()
>{
>	char	b[80]; /* Local variable */
>	/* this copies a string into your string buffer a */
>	strcpy(a,"this is a test string");
>	strcpy(b,a);	/* Copy string a into string b */
>	
>}
>-----
>
>--Chuck McManis
>uucp: {anywhere}!sun!cmcmanis   BIX: cmcmanis  ARPAnet: cmcmanis@sun.com
>These opinions are my own and no one elses, but you knew that didn't you.
>"A most excellent barbarian ... Genghis Kahn!"

I had a hard time understanding from the posting at what level "things didn't
work".  I presumed Rob had gotten the thing to compile, and the problem was with
"buffered I/O".  Since Rob had no newline characters in his test string (and
it was so short), the I/O buffers would not be flushed, and therefore he would
get no output.  I sent email suggesting this as a possible explanation.

To really be compatible with basic (since he had no newlines), I think he
would have to fflush(stdout) after every printf(), no?

for (i = 0; i < strlen(a); i++) {
  printf("%c",a[i]);
  fflush(stdout);
}

or the less obvious, but more efficient (but Chuck knows this):

char *b;

b = a;

while (*b) {
  printf("%b",*b++);
  fflush(stdout);
}

Kevin

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