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/* Copyright (C) 1991, 1993, 1996, 1997 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <unistd.h>
#include <stdarg.h>
#include <stddef.h>
#include <string.h>
/* Execute FILE, searching in the `PATH' environment variable if
it contains no slashes, with all arguments after FILE until a
NULL pointer and environment from `environ'. */
int
execlp (const char *file, const char *arg, ...)
{
size_t argv_max = 1024;
const char **argv = alloca (argv_max * sizeof (const char *));
unsigned int i;
va_list args;
argv[0] = arg;
va_start (args, arg);
i = 1;
do
{
if (i == argv_max)
{
const char **nptr = alloca ((argv_max *= 2) * sizeof (const char *));
if ((char *) nptr + argv_max == (char *) argv)
{
/* Stack grows down. */
argv = (const char **) memcpy (nptr, argv, i);
argv_max += i;
}
else if ((char *) argv + i == (char *) nptr)
/* Stack grows up. */
argv_max += i;
else
/* We have a hole in the stack. */
argv = (const char **) memcpy (nptr, argv, i);
}
argv[i] = va_arg (args, const char *);
}
while (argv[i++] != NULL);
va_end (args);
return execvp (file, (char *const *) argv);
}
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