UNIX 7th Ed. - /usr/src/libc/sys/dup.s

   1: / C library -- dup
   2: 
   3: /	f = dup(of [ ,nf])
   4: /	f == -1 for error
   5: 
   6: .globl  _dup,_dup2
   7: .globl  cerror
   8: .dup = 41.
   9: 
  10: _dup2:
  11:         mov     r5,-(sp)
  12:         mov     sp,r5
  13:         mov     4(r5),r0
  14:         bis     $100,r0
  15:         br      1f
  16: 
  17: _dup:
  18:         mov     r5,-(sp)
  19:         mov     sp,r5
  20:         mov     4(r5),r0
  21: 1:
  22:         mov     6(r5),r1
  23:         sys     .dup
  24:         bec     1f
  25:         jmp     cerror
  26: 1:
  27:         mov     (sp)+,r5
  28:         rts     pc

Defined functions