diff --git a/src/liblimb/djbunix.h/sa_readmax.c b/src/liblimb/djbunix.h/sa_readmax.c
new file mode 100644
index 0000000..4c8e804
--- /dev/null
+++ b/src/liblimb/djbunix.h/sa_readmax.c
@@ -0,0 +1,32 @@
+/* This file is part of limb                           https://lila.oss/limb
+ * Copyright (C) 2023 Olivier Brunel                          jjk@jjacky.com */
+/* SPDX-License-Identifier: GPL-2.0-only */
+#include <errno.h>
+#include <limb/allreadwrite.h>
+#include <limb/djbunix.h>
+
+int
+sa_readmax(stralloc *sa, int fd, size_t max)
+{
+    size_t salen = sa->len;
+    for (;;)
+    {
+        size_t n = max && sa->len - salen + 4096 > max ? max - (sa->len - salen) : 4096;
+        if (!n) {
+            errno = ENOBUFS;
+            break;
+        }
+        if (!stralloc_readyplus(sa, n)) break;
+
+        ssize_t r = fd_read(fd, sa->s + sa->len, n) ;
+        switch (r)
+        {
+            case -1: break;
+            case 0:  return 1;
+            default: sa->len += r;
+        }
+    }
+
+    sa->len = salen;
+    return 0;
+}
diff --git a/src/liblimb/include/limb/djbunix.h b/src/liblimb/include/limb/djbunix.h
index 7fcf1a4..21bc86d 100644
--- a/src/liblimb/include/limb/djbunix.h
+++ b/src/liblimb/include/limb/djbunix.h
@@ -38,8 +38,8 @@ extern int openc_exclat(int fd, const char *file);
 extern int open_parsed_name(const char *name, open_fn open);
 
 #define read_close(dst,dlen,fd) readnclose(fd, dst, dlen)
-#define sa_read(sa,fd)          slurpn(fd, sa, 0)
-#define sa_readmax(sa,fd,max)   slurpn(fd, sa, max)
+extern int sa_readmax(stralloc *sa, int fd, size_t max);
+#define sa_read(sa,fd)          sa_readmax(sa, fd, 0)
 
 extern ssize_t open_read_closeat(char *dst, size_t dlen, int bfd, const char *file);
 extern int open_saread_closeat(stralloc *sa, int bfd, const char *file);