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/*
* uw_env - environment manipulation
*
* Copyright 1985,1986 by John D. Bruner. All rights reserved. Permission to
* copy this program is given provided that the copy is not sold and that
* this copyright notice is included.
*/
#define MAXENV 128 /* maximum number of arguments in environment */
static char *earray[MAXENV+1];
env_set(env)
char **env;
{
register char **ep1, **ep2, *cp;
char **ep3;
extern char **environ;
/*
* Merge the set of environment strings in "env" into the
* environment.
*/
/*
* The first time through, copy the environment from its
* original location to the array "earray". This makes it a
* little easier to change things.
*/
if (environ != earray) {
ep1=environ;
ep2=earray;
while(*ep1 && ep2 <= earray+MAXENV)
*ep2++ = *ep1++;
*ep2++ = (char *)0;
environ = earray;
}
/*
* If "env" is non-NULL, it points to a list of new items to
* be added to the environment. These replace existing items
* with the same name.
*/
if (env) {
for (ep1=env; *ep1; ep1++) {
for (ep2=environ; *ep2; ep2++)
if (!env_cmp(*ep1, *ep2))
break;
if (ep2 < earray+MAXENV) {
if (!*ep2)
ep2[1] = (char *)0;
*ep2 = *ep1;
}
}
}
/* Finally, use an insertion sort to put things in order. */
for (ep1=environ+1; cp = *ep1; ep1++) {
for(ep2=environ; ep2 < ep1; ep2++)
if (env_cmp(*ep1, *ep2) < 0)
break;
ep3 = ep2;
for(ep2=ep1; ep2 > ep3; ep2--)
ep2[0] = ep2[-1];
*ep2 = cp;
}
}
static
env_cmp(e1, e2)
register char *e1, *e2;
{
register d;
do {
if (d = *e1 - *e2++)
return(d);
} while (*e1 && *e1++ != '=');
return(0);
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.