source: trunk/third/sysinfo/getenv.c @ 12269

/*
 * Copyright (c) 1992-1998 Michael A. Cooper.
 * This software may be freely used and distributed provided it is not
 * sold for profit or used in part or in whole for commercial gain
 * without prior written agreement, and the author is credited
 * appropriately.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)getenv.c    5.8 (Berkeley) 2/23/91";
static char rcsid[] = "$Revision: 1.1.1.2 $";
#endif /* LIBC_SCCS and not lint */

#include <stdlib.h>
#include <stddef.h>
#include <string.h>

#if     defined(notdef)
/*
 * getenv --
 *      Returns ptr to value associated with name, if any, else NULL.
 */
char *
getenv(name)
        const char *name;
{
        int offset;
        char *_findenv();

        return(_findenv(name, &offset));
}
#endif  /* notdef */

/*
 * _findenv --
 *      Returns pointer to value associated with name, if any, else NULL.
 *      Sets offset to be the offset of the name/value combination in the
 *      environmental array, for use by setenv(3) and unsetenv(3).
 *      Explicitly removes '=' in argument name.
 *
 *      This routine *should* be a static; don't use it.
 */
char *
_findenv(name, offset)
        register char *name;
        int *offset;
{
        extern char **environ;
        register int len;
        register char **P, *C;

        for (C = name, len = 0; *C && *C != '='; ++C, ++len);
        for (P = environ; *P; ++P)
                if (!strncmp(*P, name, len))
                        if (*(C = *P + len) == '=') {
                                *offset = P - environ;
                                return(++C);
                        }
        return(NULL);
}