diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 2ee7f4da3..3898a9587 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -180,7 +180,6 @@ set(RTAGS_SOURCES
     ListSymbolsJob.cpp
     Location.cpp
     Preprocessor.cpp
-    ProcThread.cpp
     Project.cpp
     QueryJob.cpp
     QueryMessage.cpp
diff --git a/src/ProcThread.cpp b/src/ProcThread.cpp
deleted file mode 100644
index 84dbc5603..000000000
--- a/src/ProcThread.cpp
+++ /dev/null
@@ -1,237 +0,0 @@
-/* This file is part of RTags (http://rtags.net).
-
-   RTags is free software: you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation, either version 3 of the License, or
-   (at your option) any later version.
-
-   RTags is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with RTags.  If not, see <http://www.gnu.org/licenses/>. */
-
-#include "ProcThread.h"
-#include <rct/StopWatch.h>
-#include "RTags.h"
-#ifdef RTAGS_HAS_PROC
-#include <sys/types.h>
-#include <dirent.h>
-#endif
-
-ProcThread::ProcThread(int interval)
-    : Thread(), mInterval(interval)
-{
-#ifdef RTAGS_HAS_PROC
-    mPath = "/proc/";
-#endif
-}
-
-ProcThread::~ProcThread()
-{
-}
-
-void ProcThread::run()
-{
-    while (true) {
-        {
-            std::unique_lock<std::mutex> lock(mMutex);
-            if (!mInterval) {
-                break;
-            }
-            if (mCond.wait_for(lock, std::chrono::milliseconds(mInterval)) != std::cv_status::timeout) {
-                break;
-            }
-        }
-        readProc();
-    }
-}
-
-void ProcThread::stop()
-{
-    {
-        std::unique_lock<std::mutex> lock(mMutex);
-        mInterval = 0;
-        mCond.notify_one();
-    }
-    join();
-}
-
-struct ParseNode {
-    char cmdLine[16384];
-    char cwd[PATH_MAX];
-    List<String> environ;
-
-};
-void ProcThread::readProc()
-{
-    for (auto &pair : mNodes) {
-        pair.second = true;
-    }
-#ifdef RTAGS_HAS_PROC
-    DIR *dir = opendir("/proc/");
-    int found = 0;
-    StopWatch sw;
-    List<ParseNode> nodes(1);
-    while (const dirent *p = readdir(dir)) {
-#if defined(_DIRENT_HAVE_D_TYPE) && defined(_BSD_SOURCE)
-        if (p->d_type != DT_DIR)
-            continue;
-#endif
-        const int pid = atoi(p->d_name);
-        if (!pid)
-            continue;
-        auto it = mNodes.find(pid);
-        if (it != mNodes.end()) {
-            it->second = false;
-            continue;
-        } else {
-            mNodes[pid] = false;
-        }
-
-        char file[PATH_MAX]; // should be enough for everyone
-        snprintf(file, sizeof(file), "/proc/%s/cmdline", p->d_name);
-        FILE *f = fopen(file, "r");
-        if (!f) {
-            // error("Can't open %s for reading", file);
-            continue;
-        }
-
-        auto &node = nodes.back();
-
-        size_t read = fread(node.cmdLine, 1, sizeof(node.cmdLine), f);
-        fclose(f);
-        if (!read) {
-            // error("Can't read from %s", file);
-            continue;
-        }
-
-        if (!strncmp(node.cmdLine, "/bin/bash", 9) || !strncmp(node.cmdLine, "/bin/sh", 7))
-            continue;
-
-        while (read > 0 && !node.cmdLine[read-1])
-            --read; // skip trailing zeroes
-        const char *prev = node.cmdLine;
-        enum {
-            Dunno,
-            Yay,
-            Nay
-        } hasSource = Dunno;
-        for (size_t i=0; i<read; ++i) {
-            switch (node.cmdLine[i]) {
-            case '\n':
-            case '\0':
-            case ' ':
-                if (prev == node.cmdLine) {
-                    node.cmdLine[i] = '\0';
-                    // error() << "Considering" << node.cmdLine;
-                    if (strstr(node.cmdLine, "cc1plus") || strstr(node.cmdLine, "/rc")) {
-                        hasSource = Nay;
-                    }
-                }
-                node.cmdLine[i] = ' ';
-                if (i && hasSource == Dunno) {
-                    for (const char *ext = &node.cmdLine[i - 1]; ext > prev; --ext) {
-                        if (*ext == '.') {
-                            char extBuf[16];
-                            const size_t size = i - 1 - (ext - node.cmdLine);
-                            if (size < sizeof(extBuf)) {
-                                memcpy(extBuf, ext + 1, size);
-                                extBuf[size] = '\0';
-                                if (Path::isSource(extBuf)) {
-                                    hasSource = Yay;
-                                }
-                            }
-                            break;
-                        }
-                    }
-                }
-                prev = &node.cmdLine[i];
-            default:
-                break;
-            }
-        }
-        if (hasSource != Yay)
-            continue;
-
-        // error() << "GOT SOURCE" << node.cmdLine;
-
-        snprintf(file, sizeof(file), "/proc/%s/cwd", p->d_name);
-        const int w = readlink(file, node.cwd, sizeof(node.cwd) - 2);
-        if (w <= 0) {
-            // error("Can't follow link from %s", file);
-            continue;
-        }
-
-        if (node.cwd[w - 1] != '/') {
-            node.cwd[w] = '/';
-            node.cwd[w + 1] = '\0';
-        } else {
-            node.cwd[w] = '\0';
-        }
-
-        snprintf(file, sizeof(file), "/proc/%s/environ", p->d_name);
-        f = fopen(file, "r");
-        if (!f) {
-            // error("Can't open file %s", file);
-            continue;
-        }
-
-        char env[16384];
-        read = fread(env, 1, sizeof(env), f);
-        fclose(f);
-        if (!read) {
-            // error("Can't read from from %s", file);
-            continue;
-        }
-
-        while (read > 0 && !node.cmdLine[read-1])
-            --read; // skip trailing zeroes
-        size_t last = 0;
-        for (size_t i=0; i<read; ++i) {
-            switch (env[i]) {
-            case '\n':
-            case '\0':
-                node.environ.append(String(env + last, i - last));
-                last = i + 1;
-                break;
-            default:
-                break;
-            }
-        }
-        if (read > last) {
-            node.environ.append(String(env + last, read - last));
-        }
-        nodes.append(ParseNode());
-        // error() << "GONNA PARSE" << node.cmdLine;
-        // if (!sources.isEmpty()) {
-        //     error() << "GOT SOURCES" << sources[0].sourceFile();
-        // }
-        ++found;
-    }
-    SourceCache cache;
-    for (size_t i=0; i<nodes.size() - 1; ++i) {
-        const auto &node = nodes.at(i);
-        List<Path> paths;
-        SourceList sources = Source::parse(node.cmdLine, node.cwd, node.environ, &paths, &cache);
-        if (sources.size()) {
-            error() << "GOT SOURCES" << node.cmdLine;
-        }
-        // error() << "GOT SOURCES" << sources.size() << "from" << node.cmdLine
-        //         << paths;
-    }
-
-    Hash<int, bool>::iterator it = mNodes.begin();
-    while (it != mNodes.end()) {
-        if (it->second) {
-            mNodes.erase(it++);
-        } else {
-            ++it;
-        }
-    }
-    // printf("%d took %llu\n", found, sw.elapsed());
-    closedir(dir);
-#endif
-}
diff --git a/src/ProcThread.h b/src/ProcThread.h
deleted file mode 100644
index d853714dc..000000000
--- a/src/ProcThread.h
+++ /dev/null
@@ -1,56 +0,0 @@
-/* This file is part of RTags (http://rtags.net).
-
-   RTags is free software: you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation, either version 3 of the License, or
-   (at your option) any later version.
-
-   RTags is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with RTags.  If not, see <http://www.gnu.org/licenses/>. */
-
-#ifndef ProcThread_h
-#define ProcThread_h
-
-#include <rct/Hash.h>
-#include <rct/Path.h>
-#include <rct/Thread.h>
-#include <rct/SignalSlot.h>
-#include <rct/String.h>
-#include <mutex>
-#include <condition_variable>
-#include <time.h>
-#include "Source.h"
-
-#if defined(OS_Linux) || defined(OS_FreeBSD) || 1
-#define RTAGS_HAS_PROC
-#endif
-
-class ProcThread : public Thread
-{
-public:
-    ProcThread(int interval);
-    ~ProcThread();
-
-    void stop();
-    virtual void run();
-    Signal<std::function<void(SourceList)> > &command() { return mCommand; }
-private:
-    void readProc();
-
-    Signal<std::function<void(SourceList)> > mCommand;
-    std::mutex mMutex;
-    std::condition_variable mCond;
-    int mInterval;
-
-#ifdef RTAGS_HAS_PROC
-    Path mPath;
-#endif
-    Hash<int, bool> mNodes;
-};
-
-#endif
diff --git a/src/Server.h b/src/Server.h
index 882a3ed57..bc5ee30db 100644
--- a/src/Server.h
+++ b/src/Server.h
@@ -36,7 +36,6 @@
 class Match;
 class CompletionThread;
 class Connection;
-class ErrorMessage;
 class IndexDataMessage;
 class QueryJob;
 class LogOutputMessage;
@@ -159,7 +158,6 @@ class Server
     void handleIndexMessage(const std::shared_ptr<IndexMessage> &message, const std::shared_ptr<Connection> &conn);
     void handleIndexDataMessage(const std::shared_ptr<IndexDataMessage> &message, const std::shared_ptr<Connection> &conn);
     void handleQueryMessage(const std::shared_ptr<QueryMessage> &message, const std::shared_ptr<Connection> &conn);
-    void handleErrorMessage(const std::shared_ptr<ErrorMessage> &message, const std::shared_ptr<Connection> &conn);
     void handleLogOutputMessage(const std::shared_ptr<LogOutputMessage> &message, const std::shared_ptr<Connection> &conn);
     void handleVisitFileMessage(const std::shared_ptr<VisitFileMessage> &message, const std::shared_ptr<Connection> &conn);
 
@@ -231,7 +229,6 @@ class Server
     Set<std::shared_ptr<Connection> > mConnections;
 
     Signal<std::function<void()> > mIndexDataMessageReceived;
-    friend void saveFileIds();
 };
 RCT_FLAGS(Server::Option);
 RCT_FLAGS(Server::FileIdsFileFlag);