You can also use Turbo C++'s execl()
function. execl()
loads and runs C:\\TC\\BIN\\tnfsv13.exe
. NULL
means there are no arguments to send to tnfsv13.exe
. If an error occurs, execl()
returns -1 into int c
.
#include<stdio.h>
#include<process.h>
int main()
{
int c = execl("C:\\TC\\BIN\\tnfsv13.exe", NULL);
return 0;
}
Explanation:
execl() loads and executes a new child process. Because the child
process is placed in the memory currently occupied by the calling
process, there must be sufficient memory to load and execute it.
'pathname' specifies the file name of the child process. If
'pathname' has a file name extension, then only that file is searched
for. If 'pathname' ends with a period (.), then 'pathname' without an
extension is searched for. If that filename is not found, then
".EXE" is appended and execl() searches again. If 'pathname' has no
extension and does not end with a period, then execl() searches for
'pathname' and, if it is not found, appends ".COM" and searches
again. If that is not found, it appends ".EXE" and searches again.
'arg0', 'arg1',...'argn' are passed to the child process as command-
line parameters. A NULL pointer must follow 'argn' to terminate the
list of arguments. 'arg0' must not be NULL, and is usually set to
'pathname'.
The combined length of all the strings forming the argument list
passed to the child process must not exceed 128 bytes. This includes
"n" (for 0-n arguments) space characters (required to separate the
arguments) but does not include the null ('\0') terminating
character.
Returns: If execl() is successful, it does not return to the
calling process. (See the spawn...() routines for a
similar function that can return to the calling
process). If an error occurs, execl() returns -1 to
the calling process. On error, 'errno' (defined in
<errno.h>) is set to one of the following values
(defined in <errno.h>):
E2BIG Argument list or environment list too big.
(List > 128 bytes, or environment > 32k)
EACCES Locking or sharing violation on file.
(MS-DOS 3.0 and later)
EMFILE Too many files open.
ENOENT File or path not found.
ENOEXEC File not executable.
ENOMEM Not enough memory.
Notes: Any file open when an exec call is made remains open
in the child process. This includes
'stdin','stdout', 'stderr', 'stdaux', and 'stdprn'.
The child process acquires the environment of the
calling process.
execl() does not preserve the translation modes of
open files. Use setmode() in the child process to
set the desired translation modes.
See the spawn...() routines for similar though more
flexible functions that can return to the calling
program.
Caution: The file pointers to open buffered files are not
always preserved correctly. The information in the
buffer may be lost.
Signal settings are not preserved. They are reset to
the default in the child process.
-------------------------------- Example ---------------------------------
The following statements transfer execution to the child process
"child.exe" and pass it the three arguments "child", "arg1",
and"arg2":
#include <process.h> /* for 'execl' */
#include <stdio.h> /* for 'printf' and 'NULL' */
#include <errno.h> /* for 'errno', 'ENOENT' and 'ENOMEM' */
main()
{
execl("child.exe", "child", "arg1", "arg2", NULL);
/* only get here on an exec error */
if (errno == ENOENT)
printf("child.exe not found in current directory\n");
else if (errno == ENOMEM)
printf("not enough memory to execute child.exe\n");
else
printf(" error #%d trying to exec child.exe\n", errno);
}