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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: forking madness
Date: Tue, 03 Mar 2015 09:44:31 -0800
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Lőrinczy Zsigmond <nospam@for.me> writes:
> I don't really get what your question is, but I suggest
> you don't use printf/puts when multiprocessing,
> instead try something like this
> (handle==1 for stdout, handle==2 for stderr):
>
> static void mylog (int handle, const char *fmt, ...)
> {
>     char buff [1024];
>     int len;
>     va_list ap;
>
>     va_start (ap, fmt);
>     len= vsnprintf (buff, sizeof (buff), fmt, ap);
>     va_end (ap);
>     if (len<0 || (size_t)len>=sizeof (buff)) len= (int)sizeof(buff);
>     write (handle, buff, len);
> }
>
> Note: if you want to write into file, use append mode
> (eg ./myprog >>logfile) not to lose messages.

I presume the point of that is to avoid buffering, so output appears
immediately.

What is the advantage of your (POSIX-only) solution over the standard

    printf("Your message here\n");
    fflush(stdout);

?

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"