Plan 9 from Bell Labs’s /usr/web/sources/plan9/sys/src/libc/9sys/sysname.c
#include <u.h> #include <libc.h> char* sysname(void) { int f, n; static char b[128]; if(b[0]) return b; f = open("#c/sysname", 0); if(f >= 0) { n = read(f, b, sizeof(b)-1); if(n > 0) b[n] = 0; close(f); } return b; }