update doc and apply oneshot() where necessary

4 files changed, 108 insertions, 103 deletions

diff --git a/scripts/iotop.py b/scripts/iotop.py
index 200926ed..1a8d8ba5 100755
--- a/scripts/iotop.py
+++ b/scripts/iotop.py
@@ -111,14 +111,15 @@ def poll(interval):
 
     # then retrieve the same info again
     for p in procs[:]:
-        try:
-            p._after = p.io_counters()
-            p._cmdline = ' '.join(p.cmdline())
-            if not p._cmdline:
-                p._cmdline = p.name()
-            p._username = p.username()
-        except (psutil.NoSuchProcess, psutil.ZombieProcess):
-            procs.remove(p)
+        with p.oneshot():
+            try:
+                p._after = p.io_counters()
+                p._cmdline = ' '.join(p.cmdline())
+                if not p._cmdline:
+                    p._cmdline = p.name()
+                p._username = p.username()
+            except (psutil.NoSuchProcess, psutil.ZombieProcess):
+                procs.remove(p)
     disks_after = psutil.disk_io_counters()
 
     # finally calculate results by comparing data before and
diff --git a/scripts/pidof.py b/scripts/pidof.py
index 8692a315..0db9563e 100755
--- a/scripts/pidof.py
+++ b/scripts/pidof.py
@@ -19,23 +19,24 @@ import sys
 def pidof(pgname):
     pids = []
     for proc in psutil.process_iter():
-        # search for matches in the process name and cmdline
-        try:
-            name = proc.name()
-        except psutil.Error:
-            pass
-        else:
-            if name == pgname:
-                pids.append(str(proc.pid))
-                continue
-
-        try:
-            cmdline = proc.cmdline()
-        except psutil.Error:
-            pass
-        else:
-            if cmdline and cmdline[0] == pgname:
-                pids.append(str(proc.pid))
+        with proc.oneshot():
+            # search for matches in the process name and cmdline
+            try:
+                name = proc.name()
+            except psutil.Error:
+                pass
+            else:
+                if name == pgname:
+                    pids.append(str(proc.pid))
+                    continue
+
+            try:
+                cmdline = proc.cmdline()
+            except psutil.Error:
+                pass
+            else:
+                if cmdline and cmdline[0] == pgname:
+                    pids.append(str(proc.pid))
 
     return pids
 
diff --git a/scripts/procsmem.py b/scripts/procsmem.py
index 494fd6ab..7c14dca3 100755
--- a/scripts/procsmem.py
+++ b/scripts/procsmem.py
@@ -61,41 +61,42 @@ def main():
     ad_pids = []
     procs = []
     for p in psutil.process_iter():
-        try:
-            mem = p.memory_full_info()
-            info = p.as_dict(attrs=["cmdline", "username"])
-        except psutil.AccessDenied:
-            ad_pids.append(p.pid)
-        except psutil.NoSuchProcess:
-            pass
-        else:
-            p._uss = mem.uss
-            p._rss = mem.rss
-            if not p._uss:
-                continue
-            p._pss = getattr(mem, "pss", "")
-            p._swap = getattr(mem, "swap", "")
-            p._info = info
-            procs.append(p)
-
-    procs.sort(key=lambda p: p._uss)
-    templ = "%-7s %-7s %-30s %7s %7s %7s %7s"
-    print(templ % ("PID", "User", "Cmdline", "USS", "PSS", "Swap", "RSS"))
-    print("=" * 78)
-    for p in procs:
-        line = templ % (
-            p.pid,
-            p._info["username"][:7],
-            " ".join(p._info["cmdline"])[:30],
-            convert_bytes(p._uss),
-            convert_bytes(p._pss) if p._pss != "" else "",
-            convert_bytes(p._swap) if p._swap != "" else "",
-            convert_bytes(p._rss),
-        )
-        print(line)
-    if ad_pids:
-        print("warning: access denied for %s pids" % (len(ad_pids)),
-              file=sys.stderr)
+        with p.oneshot():
+            try:
+                mem = p.memory_full_info()
+                info = p.as_dict(attrs=["cmdline", "username"])
+            except psutil.AccessDenied:
+                ad_pids.append(p.pid)
+            except psutil.NoSuchProcess:
+                pass
+            else:
+                p._uss = mem.uss
+                p._rss = mem.rss
+                if not p._uss:
+                    continue
+                p._pss = getattr(mem, "pss", "")
+                p._swap = getattr(mem, "swap", "")
+                p._info = info
+                procs.append(p)
+
+        procs.sort(key=lambda p: p._uss)
+        templ = "%-7s %-7s %-30s %7s %7s %7s %7s"
+        print(templ % ("PID", "User", "Cmdline", "USS", "PSS", "Swap", "RSS"))
+        print("=" * 78)
+        for p in procs:
+            line = templ % (
+                p.pid,
+                p._info["username"][:7],
+                " ".join(p._info["cmdline"])[:30],
+                convert_bytes(p._uss),
+                convert_bytes(p._pss) if p._pss != "" else "",
+                convert_bytes(p._swap) if p._swap != "" else "",
+                convert_bytes(p._rss),
+            )
+            print(line)
+        if ad_pids:
+            print("warning: access denied for %s pids" % (len(ad_pids)),
+                  file=sys.stderr)
 
 if __name__ == '__main__':
     sys.exit(main())
diff --git a/scripts/ps.py b/scripts/ps.py
index 9143a557..f3063ade 100755
--- a/scripts/ps.py
+++ b/scripts/ps.py
@@ -29,52 +29,54 @@ def main():
     print(templ % ("USER", "PID", "%CPU", "%MEM", "VSZ", "RSS", "TTY",
                    "START", "TIME", "COMMAND"))
     for p in psutil.process_iter():
-        try:
-            pinfo = p.as_dict(attrs, ad_value='')
-        except psutil.NoSuchProcess:
-            pass
-        else:
-            if pinfo['create_time']:
-                ctime = datetime.datetime.fromtimestamp(pinfo['create_time'])
-                if ctime.date() == today_day:
-                    ctime = ctime.strftime("%H:%M")
-                else:
-                    ctime = ctime.strftime("%b%d")
-            else:
-                ctime = ''
-            cputime = time.strftime("%M:%S",
-                                    time.localtime(sum(pinfo['cpu_times'])))
+        with p.oneshot():
             try:
-                user = p.username()
-            except KeyError:
-                if os.name == 'posix':
-                    if pinfo['uids']:
-                        user = str(pinfo['uids'].real)
+                pinfo = p.as_dict(attrs, ad_value='')
+            except psutil.NoSuchProcess:
+                pass
+            else:
+                if pinfo['create_time']:
+                    ctime = datetime.datetime.fromtimestamp(
+                        pinfo['create_time'])
+                    if ctime.date() == today_day:
+                        ctime = ctime.strftime("%H:%M")
                     else:
-                        user = ''
+                        ctime = ctime.strftime("%b%d")
                 else:
-                    raise
-            except psutil.Error:
-                user = ''
-            if os.name == 'nt' and '\\' in user:
-                user = user.split('\\')[1]
-            vms = pinfo['memory_info'] and \
-                int(pinfo['memory_info'].vms / 1024) or '?'
-            rss = pinfo['memory_info'] and \
-                int(pinfo['memory_info'].rss / 1024) or '?'
-            memp = pinfo['memory_percent'] and \
-                round(pinfo['memory_percent'], 1) or '?'
-            print(templ % (
-                user[:10],
-                pinfo['pid'],
-                pinfo['cpu_percent'],
-                memp,
-                vms,
-                rss,
-                pinfo.get('terminal', '') or '?',
-                ctime,
-                cputime,
-                pinfo['name'].strip() or '?'))
+                    ctime = ''
+                cputime = time.strftime(
+                    "%M:%S", time.localtime(sum(pinfo['cpu_times'])))
+                try:
+                    user = p.username()
+                except KeyError:
+                    if os.name == 'posix':
+                        if pinfo['uids']:
+                            user = str(pinfo['uids'].real)
+                        else:
+                            user = ''
+                    else:
+                        raise
+                except psutil.Error:
+                    user = ''
+                if os.name == 'nt' and '\\' in user:
+                    user = user.split('\\')[1]
+                vms = pinfo['memory_info'] and \
+                    int(pinfo['memory_info'].vms / 1024) or '?'
+                rss = pinfo['memory_info'] and \
+                    int(pinfo['memory_info'].rss / 1024) or '?'
+                memp = pinfo['memory_percent'] and \
+                    round(pinfo['memory_percent'], 1) or '?'
+                print(templ % (
+                    user[:10],
+                    pinfo['pid'],
+                    pinfo['cpu_percent'],
+                    memp,
+                    vms,
+                    rss,
+                    pinfo.get('terminal', '') or '?',
+                    ctime,
+                    cputime,
+                    pinfo['name'].strip() or '?'))
 
 
 if __name__ == '__main__':