ref: 1a5cf98c99fa20d0dd0768cd9c61fab84c2a77f8
dir: /sys/src/libc/9sys/getppid.c/
#include <u.h> #include <libc.h> int getppid(void) { char b[20]; int f; memset(b, 0, sizeof(b)); f = open("/dev/ppid", 0); if(f >= 0) { read(f, b, sizeof(b)); close(f); } return atol(b); }