Ref, incref, decref - reference counts

int incref(Ref *r)

int decref(Ref *r)

A Ref structure holds a reference count for a data structure: .EX typedef struct struct Ref { Lock; long ref; } Ref;

The reference count proper is found in ref ; the Lock prevents concurrent updates (see lock (9)).

Incref atomically increments the reference count r , and returns the new count.

Decref atomically decrements the reference count r , and returns the new count.

Release a structure containing a Ref on last use. .EX if(decref(s) == 0) free(s); /sys/src/9/port/chan.c Decref will panic (9) if the count goes negative, revealing a reference counting bug.