/ / PDP-11 C. / Standard Library. / / Ungetc. / .globl ungetc / / Ungetc(c, ioptr); / char c; / FILE *ioptr; / ungetc: jsr r0,_save mov 12(r5),r0 mov 14(r5),r4 cmp V_UGET(r4),$-1 bne 0f mov r0,V_UGET(r4) jmp _ret 0: iot