ref: 6e99e7dcbb822d9d732f3a4da1c2447fd53bfbb0
dir: /sys/src/libstdio/tmpnam.c/
/* * pANS stdio -- tmpnam */ #include "iolib.h" char *tmpnam(char *s){ static char name[]="/tmp/tn000000000000"; char *p; do{ p=name+7; while(*p=='9') *p++='0'; if(*p=='\0') return NULL; ++*p; }while(access(name, 0)==0); if(s){ strcpy(s, name); return s; } return name; }