From 1d8d69bf0692fd80781593312189256c98f34478 Mon Sep 17 00:00:00 2001
From: "Valeriano A.R." <valen.alfonso@protonmail.com>
Date: Tue, 5 Aug 2025 05:34:15 +0200
Subject: [PATCH] Add sort by PID option

---
 doc/nethogs.8   |  3 +++
 src/cui.cpp     | 11 +++++++----
 src/main.cpp    |  6 +++++-
 src/nethogs.cpp |  1 +
 4 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/doc/nethogs.8 b/doc/nethogs.8
index 928fad7..cc9fca9 100644
--- a/doc/nethogs.8
+++ b/doc/nethogs.8
@@ -78,6 +78,9 @@ Show only processes with the specified pid(s).
 \fB-j\fP
 Output in JSON format.
 .TP
+\fB-z\fP
+Sort by PID.
+.TP
 \fB-f\fP
 EXPERIMENTAL: specify string pcap filter (like tcpdump). This may be removed or changed in a future version.
 .TP
diff --git a/src/cui.cpp b/src/cui.cpp
index e975d2f..f8fd0ae 100644
--- a/src/cui.cpp
+++ b/src/cui.cpp
@@ -44,6 +44,7 @@ extern Process *unknownudp;
 extern Process *unknownip;
 
 extern bool sortRecv;
+extern bool sortPID;
 
 extern int viewMode;
 extern bool showcommandline;
@@ -97,8 +98,6 @@ public:
   double sent_value;
   double recv_value;
   const char *devicename;
-
-private:
   const char *m_name;
   const char *m_cmdline;
   pid_t m_pid;
@@ -300,14 +299,18 @@ int GreatestFirst(const void *ma, const void *mb) {
   Line *a = *pa;
   Line *b = *pb;
   double aValue;
-  if (sortRecv) {
+  if (sortPID) {
+    aValue = a->m_pid;
+  } else if (sortRecv) {
     aValue = a->recv_value;
   } else {
     aValue = a->sent_value;
   }
 
   double bValue;
-  if (sortRecv) {
+  if (sortPID) {
+    bValue = (double)b->m_pid;
+  } else if (sortRecv) {
     bValue = b->recv_value;
   } else {
     bValue = b->sent_value;
diff --git a/src/main.cpp b/src/main.cpp
index 5cc9316..1ee9658 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -70,6 +70,7 @@ static void help(bool iserror) {
   output << " m: switch between total (kB, bytes, MB) and throughput (kB/s, "
             " MB/s, GB/s) mode\n";
   output << " j: json output\n";
+  output << " z: sort by PIDn";
 }
 
 void quit_cb(int /* i */) {
@@ -154,7 +155,7 @@ int main(int argc, char **argv) {
   int garbage_collection_period = 50;
 
   int opt;
-  while ((opt = getopt(argc, argv, "Vhxtpsd:v:c:laf:Cbg:P:j")) != -1) {
+  while ((opt = getopt(argc, argv, "Vhxtpsd:v:c:laf:Cbg:P:jz")) != -1) {
     switch (opt) {
     case 'V':
       versiondisplay();
@@ -208,6 +209,9 @@ int main(int argc, char **argv) {
     case 'j':
       output_json = true;
       break;
+    case 'z':
+      sortPID = true;
+      break;
     default:
       help(true);
       exit(EXIT_FAILURE);
diff --git a/src/nethogs.cpp b/src/nethogs.cpp
index b120699..ebab94f 100644
--- a/src/nethogs.cpp
+++ b/src/nethogs.cpp
@@ -59,6 +59,7 @@ bool tracemode = false;
 bool bughuntmode = false;
 // sort on sent or received?
 bool sortRecv = true;
+bool sortPID = false;
 bool showcommandline = false;
 bool showBasename = false;
 // viewMode: kb/s or total