--- procmail-3.22/src/mailfold.c.truncate	2007-03-27 13:24:05.000000000 +0200

+++ procmail-3.22/src/mailfold.c	2007-03-27 13:25:06.000000000 +0200

@@ -30,6 +30,7 @@

 int logopened,rawnonl;

 off_t lasttell;

+static int trunced;

 static long lastdump;

 static volatile int mailread;	/* if the mail is completely read in already */

 static struct dyna_array confield;		  /* escapes, concatenations */

@@ -81,6 +82,7 @@

  long len;

 { int i;long part;

   lasttell=i= -1;SETerrno(EBADF);

+  trunced=0;

   if(s>=0)

    { if(ft_lock(type)&&(lseek(s,(off_t)0,SEEK_END),fdlock(s)))

 	nlog("Kernel-lock failed\n");

@@ -120,13 +122,18 @@

       }

 writefin:

      i=type!=ft_PIPE&&fsync(s)&&errno!=EINVAL;	  /* EINVAL => wasn't a file */

+     if ((i||len)&&lasttell>=0)

+      { int serrno=errno;

+	if(!ftruncate(s,lasttell)) trunced=1;

+	SETerrno(serrno);

+      }

      if(ft_lock(type))

       { int serrno=errno;		       /* save any error information */

 	if(fdunlock())

 	   nlog("Kernel-unlock failed\n");

 	SETerrno(serrno);

       }

-     i=rclose(s)||i;

+     i=rclose(s)||i; /* if this fails, we should truncate, but it's too late */

    }			   /* return an error even if nothing was to be sent */

   return i&&!len?-1:len;

 }

@@ -237,7 +244,7 @@

 #endif

 	      default:writeerr(buf);

 	    }

-	   if(lasttell>=0&&!truncate(boxname,lasttell)&&(logopened||verbose))

+	   if(lasttell>=0&&trunced&&(logopened||verbose))

 	      nlog("Truncated file to former size\n");	    /* undo garbage */

 ret0:	   return 0;

 	 }