#include <stdio.h>
#include <string.h>

char *getenv2(char *nam)
{
	static char buf_ret[256];
	char buf_cmd[256];

	snprintf(buf_cmd, sizeof(buf_cmd), "echo ${%s}", nam);
	FILE *f = popen(buf_cmd, "r");
	char *ret = fgets(buf_ret, sizeof(buf_ret), f);
	pclose(f);

	char *nl;
	if(ret && (nl = strrchr(ret, '\n')))
		*nl = '\0';

	return ret;
}

main()
{
	printf("%s\n", getenv2("HOME"));
}