ref: 8a788aea84aad3bfbd5b39d78c1925654f3b9e14
dir: /man/10/ref/
.TH REF 10.2 .SH NAME Ref, incref, decref \- reference counts .SH SYNOPSIS .ta \w'\fLchar* 'u .PP .B int incref(Ref *r) .PP .B int decref(Ref *r) .SH DESCRIPTION A .B Ref structure holds a reference count for a data structure: .IP .EX typedef struct struct Ref { Lock; long ref; } Ref; .EE .PP The reference count proper is found in .BR ref ; the .B Lock prevents concurrent updates (see .IR lock (10.2)). .PP .I Incref atomically increments the reference count .IR r , and returns the new count. .PP .I Decref atomically decrements the reference count .IR r , and returns the new count. .SH EXAMPLES Release a structure containing a .B Ref on last use. .IP .EX if(decref(s) == 0) free(s); .EE .SH DIAGNOSTICS .I Decref will .IR panic (10.2) if the count goes negative, revealing a reference counting bug. .SH SOURCE .B /os/port/chan.c .br .B /emu/port/chan.c