Add new user mode option -ignore-environment

An empty environment is sometimes useful in user mode.
The new option provides it for linux-user and bsd-user
(darwin-user still has no environment related options).

The patch also adds the documentation for other
environment related options.

Signed-off-by: Stefan Weil <weil@mail.berlios.de>

1 files changed, 6 insertions, 0 deletions

diff --git a/bsd-user/main.c b/bsd-user/main.c
index aff9f13b1..6b12f8bba 100644
--- a/bsd-user/main.c
+++ b/bsd-user/main.c
@@ -795,6 +795,12 @@ int main(int argc, char **argv)
             r = argv[optind++];
             if (envlist_setenv(envlist, r) != 0)
                 usage();
+        } else if (!strcmp(r, "ignore-environment")) {
+            envlist_free(envlist);
+            if ((envlist = envlist_create()) == NULL) {
+                (void) fprintf(stderr, "Unable to allocate envlist\n");
+                exit(1);
+            }
         } else if (!strcmp(r, "U")) {
             r = argv[optind++];
             if (envlist_unsetenv(envlist, r) != 0)