libbb: modify find_executable() to not temporarily write to PATH

This allows to simplify "which" applet code

function                                             old     new   delta
find_executable                                       93     111     +18
which_main                                           191     177     -14
builtin_source                                       316     294     -22
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/2 up/down: 18/-36)            Total: -18 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/include/libbb.h b/include/libbb.h
index f5f8e1635..4d6193795 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -1227,7 +1227,7 @@ void FAST_FUNC update_utmp_DEAD_PROCESS(pid_t pid);
 
 
 int file_is_executable(const char *name) FAST_FUNC;
-char *find_executable(const char *filename, char **PATHp) FAST_FUNC;
+char *find_executable(const char *filename, const char **PATHp) FAST_FUNC;
 int executable_exists(const char *filename) FAST_FUNC;
 
 /* BB_EXECxx always execs (it's not doing NOFORK/NOEXEC stuff),