--- Src/builtin.c	5 Oct 2004 10:39:43 -0000	1.129
+++ Src/builtin.c	18 Oct 2004 04:28:36 -0000
@@ -1445,7 +1445,7 @@ bin_fc(char *nam, char **argv, Options o
 	char *fil;
 
 	retval = 1;
-	fil = gettempname();
+	fil = gettempname(NULL, 1);
 	if (((tempfd = open(fil, O_WRONLY | O_CREAT | O_EXCL | O_NOCTTY, 0600))
 	     == -1) ||
 	    ((out = fdopen(tempfd, "w")) == NULL)) {
@@ -3534,8 +3534,8 @@ bin_print(char *name, char **args, Optio
     	if ((fout = open_memstream(&buf, &mcount)) == NULL)
 	    zwarnnam(name, "open_memstream failed", NULL, 0);
 #else
-	char *tmpf = gettempname();
-    	if ((fout = fopen(tmpf, "w+")) == NULL)
+	char *tmpf = gettempname(NULL, 1);
+	if (!(fout = fdopen(open(tmpf, O_RDWR|O_CREAT|O_EXCL, 0644), "w+")))
 	    zwarnnam(name, "can't open temp file: %e", NULL, errno);
 	unlink(tmpf);
 #endif
--- Src/exec.c	8 Oct 2004 14:37:30 -0000	1.74
+++ Src/exec.c	18 Oct 2004 04:28:37 -0000
@@ -2801,7 +2801,7 @@ getherestr(struct redir *fn)
     untokenize(t);
     unmetafy(t, &len);
     t[len++] = '\n';
-    s = gettempname();
+    s = gettempname(NULL, 1);
     if (!s || (fd = open(s, O_CREAT|O_WRONLY|O_EXCL|O_NOCTTY, 0600)) == -1)
 	return -1;
     write(fd, t, len);
@@ -2975,7 +2975,7 @@ getoutputfile(char *cmd)
 	return NULL;
     if (!(prog = parsecmd(cmd)))
 	return NULL;
-    if (!(nam = gettempname()))
+    if (!(nam = gettempname(NULL, 1)))
 	return NULL;
 
     nam = ztrdup(nam);
@@ -3022,7 +3022,7 @@ getoutputfile(char *cmd)
 static char *
 namedpipe(void)
 {
-    char *tnam = gettempname();
+    char *tnam = gettempname(NULL, 1);
 
 # ifdef HAVE_MKFIFO
     if (mkfifo(tnam, 0600) < 0)
--- Src/hist.c	1 Oct 2004 19:48:53 -0000	1.54
+++ Src/hist.c	18 Oct 2004 04:28:38 -0000
@@ -2129,23 +2129,19 @@ lockhistfile(char *fn, int keep_trying)
 	return 0;
     if (!lockhistct++) {
 	struct stat sb;
-	int fd, len;
+	FILE *out;
 	char *lockfile;
 #ifdef HAVE_LINK
 	char *tmpfile;
 #endif
 
-	fn = unmeta(fn);
-	len = strlen(fn);
-	lockfile = zalloc(len + 5 + 1);
-	sprintf(lockfile, "%s.LOCK", fn);
+	lockfile = bicat(unmeta(fn), ".LOCK");
 #ifdef HAVE_LINK
-	tmpfile = zalloc(len + 10 + 1);
-	sprintf(tmpfile, "%s.%ld", fn, (long)mypid);
-	unlink(tmpfile); /* NFS's O_EXCL is often broken... */
-	if ((fd = open(tmpfile, O_WRONLY|O_CREAT|O_EXCL, 0644)) >= 0) {
-	    write(fd, tmpfile+len+1, strlen(tmpfile+len+1));
-	    close(fd);
+	tmpfile = gettempname(fn, 0);
+	out = fdopen(open(tmpfile, O_WRONLY|O_CREAT|O_EXCL, 0644), "w");
+	if (out) {
+	    fprintf(out, "%ld %s\n", (long)getpid(), getsparam("HOST"));
+	    fclose(out);
 	    while (link(tmpfile, lockfile) < 0) {
 		if (errno != EEXIST || !keep_trying)
 		    ;
@@ -2167,7 +2163,7 @@ lockhistfile(char *fn, int keep_trying)
 	}
 	free(tmpfile);
 #else /* not HAVE_LINK */
-	while ((fd = open(lockfile, O_WRONLY|O_CREAT|O_EXCL, 0644)) < 0) {
+	while (!(out = fdopen(open(lockfile, O_WRONLY|O_CREAT|O_EXCL, 0644), "w"))) {
 	    if (errno != EEXIST || !keep_trying)
 		break;
 	    if (stat(lockfile, &sb) < 0) {
@@ -2180,13 +2176,11 @@ lockhistfile(char *fn, int keep_trying)
 	    else
 		unlink(lockfile);
 	}
-	if (fd < 0)
+	if (!out)
 	    lockhistct--;
 	else {
-	    char buf[16];
-	    sprintf(buf, "%ld", (long)mypid);
-	    write(fd, buf, strlen(buf));
-	    close(fd);
+	    fprintf(out, "%ld %s\n", (long)mypid, getsparam("HOST"));
+	    fclose(out);
 	}
 #endif /* not HAVE_LINK */
 	free(lockfile);
--- Src/string.c	19 Feb 2001 10:26:54 -0000	1.4
+++ Src/string.c	18 Oct 2004 04:50:22 -0000
@@ -105,6 +105,22 @@ dyncat(char *s1, char *s2)
 
 /**/
 mod_export char *
+bicat(const char *s1, const char *s2)
+{
+    /* This version always uses permanently-allocated space. */
+    char *ptr;
+    size_t l1 = strlen(s1);
+
+    ptr = (char *)zalloc(l1 + strlen(s2) + 1);
+    strcpy(ptr, s1);
+    strcpy(ptr + l1, s2);
+    return ptr;
+}
+
+/* like strdup(), but with a specified length */
+
+/**/
+mod_export char *
 dupstrpfx(const char *s, int len)
 {
     char *r = zhalloc(len + 1);
@@ -118,6 +134,7 @@ dupstrpfx(const char *s, int len)
 mod_export char *
 ztrduppfx(const char *s, int len)
 {
+    /* This version always uses permanently-allocated space. */
     char *r = zalloc(len + 1);
 
     memcpy(r, s, len);
--- Src/utils.c	18 Oct 2004 03:32:16 -0000	1.67
+++ Src/utils.c	18 Oct 2004 04:28:40 -0000
@@ -1122,28 +1122,33 @@ zclose(int fd)
     return -1;
 }
 
-/* Get a file name relative to $TMPPREFIX which *
- * is unique, for use as a temporary file.      */
- 
 #ifdef HAVE__MKTEMP
 extern char *_mktemp(char *);
 #endif
 
+/* Get a unique filename for use as a temporary file.  If "prefix" is
+ * NULL, the name is relative to $TMPPREFIX.  If "use_heap" is true, we
+ * allocate the returned name on the heap. */
+ 
 /**/
 mod_export char *
-gettempname(void)
+gettempname(const char *prefix, int use_heap)
 {
-    char *s, *ret;
+    char *ret;
  
     queue_signals();
-    if (!(s = getsparam("TMPPREFIX")))
-	s = DEFAULT_TMPPREFIX;
+    if (!prefix && !(prefix = getsparam("TMPPREFIX")))
+	prefix = DEFAULT_TMPPREFIX;
+    if (use_heap)
+	ret = dyncat(unmeta(prefix), "XXXXXX");
+    else
+	ret = bicat(unmeta(prefix), ".XXXXXX");
  
 #ifdef HAVE__MKTEMP
     /* Zsh uses mktemp() safely, so silence the warnings */
-    ret = ((char *) _mktemp(dyncat(unmeta(s), "XXXXXX")));
+    ret = (char *) _mktemp(ret);
 #else
-    ret = ((char *) mktemp(dyncat(unmeta(s), "XXXXXX")));
+    ret = (char *) mktemp(ret);
 #endif
     unqueue_signals();
 
--- Src/Modules/zftp.c	2 Jun 2004 22:15:00 -0000	1.32
+++ Src/Modules/zftp.c	18 Oct 2004 04:28:41 -0000
@@ -1971,7 +1971,7 @@ zftp_open(char *name, char **args, int f
      * However, it is closed whenever there are no connections open.
      */
     if (zfstatfd == -1) {
-	fname = gettempname();
+	fname = gettempname(NULL, 1);
 	zfstatfd = open(fname, O_RDWR|O_CREAT|O_EXCL, 0600);
 	DPUTS(zfstatfd == -1, "zfstatfd not created");
 #if defined(F_SETFD) && defined(FD_CLOEXEC)