delorie.com/archives/browse.cgi   search  
Mail Archives: cygwin/2009/11/20/03:49:49

X-Recipient: archive-cygwin AT delorie DOT com
X-SWARE-Spam-Status: No, hits=-2.2 required=5.0 tests=AWL,BAYES_00
X-Spam-Check-By: sourceware.org
MIME-Version: 1.0
Date: Fri, 20 Nov 2009 09:48:28 +0100
Reply-To: "Christian Franke" <Christian DOT Franke AT t-online DOT de>
To: "Cygwin" <cygwin AT cygwin DOT com>
Subject: execvp() runs programs from cwd even if '.' is not in PATH
From: "Christian Franke" <Christian DOT Franke AT t-online DOT de>
Message-ID: <1NBPAK-1lORIe0@fwd05.aul.t-online.de>
X-IsSubscribed: yes
Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Id: <cygwin.cygwin.com>
List-Subscribe: <mailto:cygwin-subscribe AT cygwin DOT com>
List-Archive: <http://sourceware.org/ml/cygwin/>
List-Post: <mailto:cygwin AT cygwin DOT com>
List-Help: <mailto:cygwin-help AT cygwin DOT com>, <http://sourceware.org/ml/#faqs>
Sender: cygwin-owner AT cygwin DOT com
Mail-Followup-To: cygwin AT cygwin DOT com
Delivered-To: mailing list cygwin AT cygwin DOT com

execvp() and the other 'p' variants of exec run programs also from
current directory even if '.' is not in the PATH.

The function execvp() simply calls execv(find_exec(path,
temp_path_conv_buf), argv). The function find_exec() returns the path
unchanged if not found in PATH, execv() runs the file from cwd then.


Testcase (1.5.25-15 and 1.7.0-65):

$ cd /tmp

$ cat >execvp.c <<EOF
#include <unistd.h>
#include <stdio.h>
int main(int argc, char **argv)
{
  execvp(argv[1], argv+1);
  perror(argv[1]);
  return 1;
}
EOF

$ make execvp
cc     execvp.c   -o execvp

$ cp -p /bin/echo.exe echo1.exe

$ PATH=/bin ./execvp echo1 is this a bug \?
is this a bug ?


Christian




--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple

- Raw text -


  webmaster     delorie software   privacy  
  Copyright © 2019   by DJ Delorie     Updated Jul 2019