+ int i;
+ char **ret, *p, *p2, *p3, *np, *env;
+ struct charbuf exp;
+
+ ret = szmalloc(sizeof(*ret) * (calen(sd->argv) + 1));
+ bufinit(exp);
+ for(i = 0; sd->argv[i] != NULL; i++) {
+ if((p = strchr(sd->argv[i], '$')) == NULL) {
+ ret[i] = sstrdup(sd->argv[i]);
+ } else {
+ exp.d = 0;
+ for(p2 = sd->argv[i]; p != NULL; p2 = np, p = strchr(np, '$')) {
+ bufcat(exp, p2, p - p2);
+ if(p[1] == '{') {
+ if((p3 = strchr((p += 2), '}')) == NULL) {
+ np = p;
+ break;
+ }
+ np = p3 + 1;
+ } else {
+ for(p3 = ++p; *p3; p3++) {
+ if(!(((*p3 >= 'a') && (*p3 <= 'z')) ||
+ ((*p3 >= 'A') && (*p3 <= 'Z')) ||
+ ((*p3 >= '0') && (*p3 <= '9')) ||
+ (*p3 == '_'))) {
+ break;
+ }
+ }
+ np = p3;
+ }
+ char temp[(p3 - p) + 1];
+ memcpy(temp, p, p3 - p);
+ temp[p3 - p] = 0;
+ if((env = getenv(temp)) != NULL)
+ bufcatstr(exp, env);
+ }
+ bufcatstr2(exp, np);
+ ret[i] = sstrdup(exp.b);
+ }
+ }
+ ret[i] = NULL;
+ buffree(exp);
+ return(ret);
+}
+
+struct sidata {
+ struct stdchild *sd;
+ void (*sinit)(void *);
+ void *sdata;
+};
+
+static void stdinit(void *data)
+{
+ struct sidata *d = data;
+ int i;
+
+ for(i = 0; d->sd->envp[i]; i += 2)
+ putenv(sprintf2("%s=%s", d->sd->envp[i], d->sd->envp[i + 1]));
+ if(d->sinit != NULL)
+ d->sinit(d->sdata);
+}
+
+static int stdhandle(struct child *ch, struct hthead *req, int fd, void (*chinit)(void *), void *sdata)
+{
+ struct stdchild *sd = ch->pdata;