diff --git a/libnetutil/netutil.cc b/libnetutil/netutil.cc
index 006a877ea..db10e49af 100644
--- a/libnetutil/netutil.cc
+++ b/libnetutil/netutil.cc
@@ -131,6 +131,10 @@
 #define NETINET_IP_H
 #endif
 
+#if HAVE_SYS_RESOURCE_H
+#include <sys/resource.h>
+#endif
+
 #include "netutil.h"
 
 #define NBASE_MAX_ERR_STR_LEN 1024  /* Max length of an error message */
@@ -3725,3 +3729,82 @@ char *grab_next_host_spec(FILE *inputfd, bool random, int argc, char **fakeargv)
   return host_spec;
 }
 
+
+
+/** Tries to increase the open file descriptor limit for this process.
+  * @param "desired" is the number of desired max open descriptors. Pass a
+  * negative value to set the maximum allowed.
+  * @return the number of max open descriptors that could be set, or 0 in case
+  * of failure.
+  * @warning if "desired" is less than the current limit, no action is
+  * performed. This function may only be used to increase the limit, not to
+  * decrease it. */
+int set_max_open_descriptors(int desired_max) {
+ #ifndef WIN32
+  struct rlimit r;
+  int maxfds=-1;
+  int flag=0;
+
+  #if (defined(RLIMIT_OFILE) || defined(RLIMIT_NOFILE))
+    
+    #ifdef RLIMIT_NOFILE
+        flag=RLIMIT_NOFILE; /* Linux  */
+    #else
+        flag=RLIMIT_OFILE;  /* BSD    */
+    #endif
+
+    if (!getrlimit(flag, &r)) {
+        /* If current limit is less than the desired, try to increase it */
+        if(r.rlim_cur < (rlim_t)desired_max){
+            if(desired_max<0){
+                r.rlim_cur=r.rlim_max; /* Set maximum */
+            }else{
+                r.rlim_cur = MIN( (int)r.rlim_max, desired_max );
+            }
+            if (setrlimit(flag, &r))
+               ; // netutil_debug("setrlimit(%d, %p) failed", flag, r);
+            if (!getrlimit(flag, &r)) {
+                maxfds = r.rlim_cur;
+                return maxfds;
+            }else {
+                return 0;
+            }
+        }
+    }
+
+  #endif /* (defined(RLIMIT_OFILE) || defined(RLIMIT_NOFILE)) */
+ #endif /* !WIN32 */
+ return 0;
+}
+
+
+/** Returns the open file descriptor limit for this process.
+  * @return the number of max open descriptors or 0 in case of failure. */
+int get_max_open_descriptors() {
+ #ifndef WIN32
+  struct rlimit r;
+  int flag=0;
+
+  #if (defined(RLIMIT_OFILE) || defined(RLIMIT_NOFILE))
+    
+    #ifdef RLIMIT_NOFILE
+        flag=RLIMIT_NOFILE; /* Linux  */
+    #else
+        flag=RLIMIT_OFILE;  /* BSD    */
+    #endif
+
+    if (!getrlimit(flag, &r)) {
+        return (int)r.rlim_cur;
+    }
+
+  #endif /* (defined(RLIMIT_OFILE) || defined(RLIMIT_NOFILE)) */
+ #endif /* !WIN32 */
+ return 0;
+}
+
+
+/* Maximize the open file descriptor limit for this process go up to the
+   max allowed  */
+int max_sd() {
+  return set_max_open_descriptors(-1);
+}
diff --git a/libnetutil/netutil.h b/libnetutil/netutil.h
index 5e5b55f89..b396db2a8 100644
--- a/libnetutil/netutil.h
+++ b/libnetutil/netutil.h
@@ -474,4 +474,22 @@ char *grab_next_host_spec(FILE *inputfd, bool random, int argc, char **fakeargv)
 int DnetName2PcapName(const char *dnetdev, char *pcapdev, int pcapdevlen);
 #endif
 
+/** Tries to increase the open file descriptor limit for this process.
+  * @param "desired" is the number of desired max open descriptors. Pass a
+  * negative value to set the maximum allowed.
+  * @return the number of max open descriptors that could be set, or 0 in case
+  * of failure.
+  * @warning if "desired" is less than the current limit, no action is
+  * performed. This function may only be used to increase the limit, not to
+  * decrease it. */
+int set_max_open_descriptors(int desired_max);
+
+/** Returns the open file descriptor limit for this process.
+  * @return the number of max open descriptors or 0 in case of failure. */
+int get_max_open_descriptors();
+
+/* Maximize the open file descriptor limit for this process go up to the
+   max allowed  */
+int max_sd();
+
 #endif /* _NETUTIL_H_ */
diff --git a/tcpip.cc b/tcpip.cc
index 2f56188df..d54acf807 100644
--- a/tcpip.cc
+++ b/tcpip.cc
@@ -108,10 +108,6 @@
 #include <sys/time.h>
 #endif
 
-#if HAVE_SYS_RESOURCE_H
-#include <sys/resource.h>
-#endif
-
 #if HAVE_UNISTD_H
 /* #include <sys/unistd.h> */
 #include <unistd.h>
@@ -1665,45 +1661,6 @@ void max_rcvbuf(int sd) {
 #endif /* WIN32 */
 }
 
-/* Maximize the open file descriptor limit for this process go up to the
-   max allowed  */
-int max_sd() {
-#ifndef WIN32
-  struct rlimit r;
-  static int maxfds = -1;
-
-  if (maxfds > 0)
-    return maxfds;
-
-#if(defined(RLIMIT_NOFILE))
-  if (!getrlimit(RLIMIT_NOFILE, &r)) {
-    r.rlim_cur = r.rlim_max;
-    if (setrlimit(RLIMIT_NOFILE, &r))
-      if (o.debugging)
-        perror("setrlimit RLIMIT_NOFILE failed");
-    if (!getrlimit(RLIMIT_NOFILE, &r)) {
-      maxfds = r.rlim_cur;
-      return maxfds;
-    } else
-      return 0;
-  }
-#endif
-#if(defined(RLIMIT_OFILE) && !defined(RLIMIT_NOFILE))
-  if (!getrlimit(RLIMIT_OFILE, &r)) {
-    r.rlim_cur = r.rlim_max;
-    if (setrlimit(RLIMIT_OFILE, &r))
-      if (o.debugging)
-        perror("setrlimit RLIMIT_OFILE failed");
-    if (!getrlimit(RLIMIT_OFILE, &r)) {
-      maxfds = r.rlim_cur;
-      return maxfds;
-    } else
-      return 0;
-  }
-#endif
-#endif /* WIN32 */
-  return 0;
-}
 
 /* Give broadcast permission to a socket */
 void broadcast_socket(int sd) {
diff --git a/tcpip.h b/tcpip.h
index da78c9e2a..9ab6df069 100644
--- a/tcpip.h
+++ b/tcpip.h
@@ -639,10 +639,6 @@ int gettcpopt_ts(struct tcp_hdr *tcp, u32 *timestamp, u32 *echots);
 /* Maximize the receive buffer of a socket descriptor (up to 500K) */
 void max_rcvbuf(int sd);
 
-/* Maximize the open file descriptor limit for this process go up to the
-   max allowed  */
-int max_sd();
-
 /* Give broadcast permission to a socket */
 void broadcast_socket(int sd);