1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
|
/***
*system.c - pass a command line to the shell
*
* Copyright (c) 1985-1993, Microsoft Corporation. All rights reserved.
*
*Purpose:
* defines system() - passes a command to the shell
*
*Revision History:
* 12-01-83 RN written
* 10-23-86 SKS Fixed use of strtok(), added check for NULL rtn from getenv
* 12-18-86 SKS PROTMODE symbol used for dual-modal version
* 02-23-86 JCR Put in support for NULL command pointer (MSDOS only)
* 04-13-86 JCR Added const to declaration
* 06-30-87 JCR Re-wrote system to use spawnvpe, removed XENIX conditional
* code, lots of general cleaning up.
* 07-01-87 PHG removed P->PROTMODE compile switch hack
* 09-22-87 SKS remove extern variable declarations, add ";" to assert()'s
* 11-10-87 SKS Removed IBMC20 switch, change PROTMODE to OS2
* 12-11-87 JCR Added "_LOAD_DS" to declaration
* 02-22-88 JCR Added cast to get rid of cl const warning
* 09-05-88 SKS Treat EACCES the same as ENOENT -- keep trying
* 03-08-90 GJF Replaced _LOAD_DS with _CALLTYPE1, added #include
* <cruntime.h>, removed some leftover DOS support and
* fixed the copyright. Also, cleaned up the formatting
* formatting a bit.
* 07-23-90 SBM Compiles cleanly with -W3 (removed unreferenced
* variable), removed redundant includes, replaced
* <assertm.h> by <assert.h>, minor optimizations
* 09-27-90 GJF New-style function declarator.
* 01-17-91 GJF ANSI naming.
* 02-14-90 SRW Use NULL instead of _environ to get default.
* 02-23-93 SKS Remove reference to _osmode and use of "command.com"
*
*******************************************************************************/
#include <cruntime.h>
#include <assert.h>
#include <process.h>
#include <io.h>
#include <stdlib.h>
#include <errno.h>
/***
*int system(command) - send the command line to a shell
*
*Purpose:
* Executes a shell and passes the command line to it.
* If command is NULL, determine if a command processor exists.
*
*Entry:
* char *command - command to pass to the shell (if NULL, just determine
* if command processor exists)
*
*Exit:
* if command != NULL returns status of the shell
* if command == NULL returns non-zero if CP exists, zero if CP doesn't exist
*
*Exceptions:
*
*******************************************************************************/
int _CALLTYPE1 system (
const char *command
)
{
int catch;
char *argv[4];
argv[0] = getenv("COMSPEC");
if (command == NULL) {
return (!_access(argv[0],0));
}
assert(*command != '\0');
argv[1] = "/c";
argv[2] = (char *) command;
argv[3] = NULL;
/* If there is a COMSPEC defined, try spawning the shell */
if (argv[0]) /* Do not try to spawn the null string */
if ((catch = _spawnve(_P_WAIT,argv[0],argv,NULL)) != -1
|| (errno != ENOENT && errno != EACCES))
return(catch);
/* No COMSPEC so set argv[0] to what COMSPEC should be. */
argv[0] = "cmd.exe";
/* Let the _spawnvpe routine do the path search and spawn. */
return(_spawnvpe(_P_WAIT,argv[0],argv,NULL));
}
|
