diff --git a/display.F90 b/display.F90
index 8d91c6641..b92e07cdc 100644
--- a/display.F90
+++ b/display.F90
@@ -15,6 +15,7 @@ subroutine display(nkeep,ncsmin)
   integer utc(MAXLINES),utc2(MX),utcz
   real*8 f0
 
+  call cs_lock('display')
   ftol=0.02
   rewind 26
 
@@ -167,5 +168,7 @@ subroutine display(nkeep,ncsmin)
 1040 format(a40)
   enddo
   call flushqqq(20)
-999  return
+999  continue
+  call cs_unlock
+  return
 end subroutine display
diff --git a/extract.f b/extract.f
index 91eab6c67..c08c3b17f 100644
--- a/extract.f
+++ b/extract.f
@@ -41,14 +41,18 @@
          call interleave63(mr2prob,-1)
 
          nsec1=nsec1+1
+         call cs_lock('extracta')
          write(22,rec=1) nsec1,xlambda,maxe,200,
      +        mrsym,mrprob,mr2sym,mr2prob
          call flushqqq(22)
+         call cs_unlock
          call runqqq('kvasd.exe','-q',iret)
          if(iret.ne.0) then
+            call cs_lock('extractb')
             if(first) write(*,1000) iret
  1000       format('Error in KV decoder, or no KV decoder present.'/
      +         'Return code:',i8,'.  Will use BM algorithm.')
+            call cs_unlock
             ndec=0
             first=.false.
             go to 20
diff --git a/getdphi.f90 b/getdphi.f90
index 8f0e00bdb..3d5b32f6a 100644
--- a/getdphi.f90
+++ b/getdphi.f90
@@ -11,8 +11,10 @@ subroutine getdphi(qphi)
   enddo
 
   dphi=57.2957795*atan2(s,c)
+  call cs_lock('getdphi')
   write(11,1010) nint(dphi)
 1010 format('Best-fit Dphi =',i4,' deg')
+  call cs_unlock
 
   return
   end
diff --git a/getfile2.F90 b/getfile2.F90
index 2ec0bace2..ecf17c7e4 100644
--- a/getfile2.F90
+++ b/getfile2.F90
@@ -33,7 +33,9 @@ subroutine getfile2(fname,len)
   monitoring=0
   kbuf=1
 
+  call cs_lock('getfile2a')
   call rfile3a(fname,id,n,ierr)
+  call cs_unlock
   if(ierr.ne.0) then
      print*,'Error opening or reading file: ',fname,ierr
      go to 999
@@ -48,7 +50,9 @@ subroutine getfile2(fname,len)
   enddo
   sqave=174*sq/(kb-ka+1)
   rxnoise=10.0*log10(sqave) - 48.0
+  call cs_lock('getfile2b')
   read(filename(8:11),*,err=20,end=20) nutc
+  call cs_unlock
   go to 30
 20 nutc=0
 
diff --git a/map65.py b/map65.py
index 25810b37a..646a7a18c 100644
--- a/map65.py
+++ b/map65.py
@@ -1,4 +1,4 @@
-#------------------------------------------------------------------------ MAP65
+#----------------------------------------------------------------------- MAP65
 # $Date$ $Revision$
 #
 from Tkinter import *
diff --git a/map65a.F90 b/map65a.F90
index 29976df53..6152cb919 100644
--- a/map65a.F90
+++ b/map65a.F90
@@ -269,6 +269,7 @@ subroutine map65a(newdat)
               if(decoded(1:4).eq.'RO  ' .or. decoded(1:4).eq.'RRR  ' .or.  &
                  decoded(1:4).eq.'73  ') nsync2=nsync2-6
               nwrite=nwrite+1
+              call cs_lock('map65aa')
               if(ndphi.eq.0) then
                  write(11,1010) nkHz,ndf,npol,nutc,dt,nsync2,decoded,nkv,nqual
 1010             format(i3,i5,i4,i5.4,f5.1,i4,2x,a22,i5,i4,i4)
@@ -280,12 +281,15 @@ subroutine map65a(newdat)
                       dt,sync2,nkv,nqual,decoded
 1011             format(i3,i4,i5,i4,i5.4,f5.1,f7.1,i3,i5,2x,a22)
               endif
+              call cs_unlock
            endif
         enddo
         if(nwrite.eq.0) then
            nfqso=mfqso + nfoffset
+           call cs_lock('map65ab')
            write(11,1012) nfqso,nutc
 1012          format(i3,9x,i5.4)
+           call cs_unlock
         endif
    
      endif
@@ -359,19 +363,23 @@ subroutine map65a(newdat)
            nsync2=nint(10.0*log10(sync2)) - 40 !### empirical ###
            if(decoded(1:4).eq.'RO  ' .or. decoded(1:4).eq.'RRR  ' .or.  &
                 decoded(1:4).eq.'73  ') nsync2=nsync2-6
+           call cs_lock('map65ac')
            write(26,1014) f0,ndf,ndf0,ndf1,ndf2,dt,npol,nsync1,       &
                 nsync2,nutc,decoded,nkv,nqual,nhist
            write(21,1014) f0,ndf,ndf0,ndf1,ndf2,dt,npol,nsync1,       &
                 nsync2,nutc,decoded,nkv,nqual,nhist
 1014       format(f7.3,i5,3i3,f5.1,i5,i3,i4,i5.4,2x,a22,3i3)
+           call cs_unlock
 
         endif
      endif
      j=j+nsiz(n)
   enddo
+  call cs_lock('map65ad')
   write(26,1015) nutc
 1015 format(39x,i4.4)
   call flushqqq(26)
+  call cs_unlock
   call display(nkeep,ncsmin)
   ndecdone=2
 
diff --git a/rfile.f90 b/rfile.f90
index 23258e88d..db6d64e51 100644
--- a/rfile.f90
+++ b/rfile.f90
@@ -1,12 +1,13 @@
-
-!----------------------------------------------------- rfile
 subroutine rfile(lu,ibuf,n,ierr)
 
   integer*1 ibuf(n)
 
+  call cs_lock('rfile')
   read(lu,end=998) ibuf
   ierr=0
   go to 999
 998 ierr=1002
-999  return
+999 continue
+  call cs_unlock
+  return
 end subroutine rfile
diff --git a/savetf2.F90 b/savetf2.F90
index dd840d5db..e45c95178 100644
--- a/savetf2.F90
+++ b/savetf2.F90
@@ -10,6 +10,7 @@ subroutine savetf2(id,fnamedate,savedir)
   data nloc/-1/
   save nloc
 
+  call cs_lock('savetf2')
   call date_and_time(cdate,ctime2,czone,itt)
   nh=itt(5)-itt(4)/60
   nm=itt(6)
@@ -51,5 +52,7 @@ subroutine savetf2(id,fnamedate,savedir)
 998 print*,'Cannot open file:'
   print*,fname
 
-999 return
+999 continue
+  call cs_unlock
+  return
 end subroutine savetf2
diff --git a/symspec.f90 b/symspec.f90
index a7c35035e..cb3df7fc7 100644
--- a/symspec.f90
+++ b/symspec.f90
@@ -84,10 +84,7 @@ subroutine symspec(id,kbuf,kk,kkdone,nutc,newdat)
      enddo
      nz2=nz2+n2
      pctblank=nclip*100.0/nz2
-!     write(*,3002) nblank,n2,nz2,nclip,kkk,kkdone,pctblank,sqave
-!3002 format(4i6,2i9,f8.1,f10.0)
   endif
-!###
 
   do nn=1,ntot
      i0=ts+hsym                           !Starting sample pointer
@@ -150,8 +147,10 @@ subroutine symspec(id,kbuf,kk,kkdone,nutc,newdat)
 !         if(n.eq.ntot) then
      if(n.ge.279) then
         call move(ssz5,ss5,322*NFFT)
+        call cs_lock('symspec')
         write(utcdata,1002) nutc
 1002    format(i4.4)
+        call cs_unlock
         utcdata=utcdata(1:2)//':'//utcdata(3:4)
         newspec=1
         call move(ssz,ss,4*322*NFFT)
diff --git a/wsjtgen.F90 b/wsjtgen.F90
index 664d2cc4f..d8d6f53d7 100644
--- a/wsjtgen.F90
+++ b/wsjtgen.F90
@@ -69,10 +69,12 @@ subroutine wsjtgen
         go to 14
 12      print*,'Cannot open test file ',msg(2:)
         go to 999
-14      read(18) hdr
+14      call cs_lock('wsjtgena')
+        read(18) hdr
         if(ndata.gt.NTxMax) ndata=NTxMax
         call rfile(18,iwave,ndata,ierr)
         close(18)
+        call cs_unlock
         if(ierr.ne.0) print*,'Error reading test file ',msg(2:)
         nwave=ndata/2
         do i=nwave,NTXMAX
@@ -90,13 +92,15 @@ subroutine wsjtgen
      if(msg(2:2).eq.'C' .or. msg(2:2).eq.'c') freq=1764
      if(msg(2:2).eq.'D' .or. msg(2:2).eq.'d') freq=2205
      if(freq.eq.1000.0) then
+        call cs_lock('wsjtgenb')
         read(msg(2:),*,err=1) freq
         goto 2
 1       txmsg='@1000'
         nmsg=5
         nmsg0=5
+2       call cs_unlock
      endif
-2    nwave=60*fsample_out
+     nwave=60*fsample_out
      dpha=twopi*freq/fsample_out
      do i=1,nwave
         iwave(i)=32767.0*sin(i*dpha)
@@ -108,7 +112,9 @@ subroutine wsjtgen
   if(mode(5:5).eq.'A') mode65=1
   if(mode(5:5).eq.'B') mode65=2
   if(mode(5:5).eq.'C') mode65=4
+  call cs_lock('wsjtgenc')
   call gen65(msg,mode65,samfacout,iwave,nwave,sendingsh,msgsent)
+  call cs_unlock
 
   if(lcwid) then
 !  Generate and insert the CW ID.