ref: a609c6102f28f53a9a151804998d4e4b5347ddb5
dir: /sys/src/cmd/touch.c/
#include <u.h> #include <libc.h> int touch(int, char *); ulong now; void usage(void) { fprint(2, "usage: touch [-c] [-t time] files\n"); exits("usage"); } void main(int argc, char **argv) { char *t, *s; int nocreate = 0; int status = 0; now = time(0); ARGBEGIN{ case 't': t = EARGF(usage()); now = strtoul(t, &s, 0); if(s == t || *s != '\0') usage(); break; case 'c': nocreate = 1; break; default: usage(); }ARGEND if(!*argv) usage(); while(*argv) status += touch(nocreate, *argv++); if(status) exits("touch"); exits(0); } touch(int nocreate, char *name) { Dir stbuff; int fd; nulldir(&stbuff); stbuff.mtime = now; if(dirwstat(name, &stbuff) >= 0) return 0; if(nocreate){ fprint(2, "touch: %s: cannot wstat: %r\n", name); return 1; } if((fd = create(name, OREAD|OEXCL, 0666)) < 0){ fprint(2, "touch: %s: cannot create: %r\n", name); return 1; } dirfwstat(fd, &stbuff); close(fd); return 0; }