我正在尝试使用内置命令创建一个基本
shell,我遇到了一些getopt问题.这是输出(使用valgrind)：
$mkdir -p foo/bar mkdir -p foo/bar FLAGON $mkdir -p foo/test mkdir -p foo/test ==15377== Invalid read of size 1 ==15377== at 0x5201BBE: _getopt_internal_r (in /usr/lib/libc-2.17.so) ==15377== by 0x5202CEA: _getopt_internal (in /usr/lib/libc-2.17.so) ==15377== by 0x5202D37: getopt (in /usr/lib/libc-2.17.so) ==15377== by 0x40351A: shell_ns_cmd_mkdir (shell.c:542) ==15377== by 0x403AB4: normal_shell_cb (shell.c:610) ==15377== by 0x402E8E: shell_mainloop (shell.c:402) ==15377== by 0x401B67: main (main.c:52) ==15377== Address 0x54e0912 is 2 bytes inside a block of size 3 free'd ==15377== at 0x4C2AD3C: free (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so) ==15377== by 0x402C93: shell_mainloop (shell.c:384) ==15377== by 0x401B67: main (main.c:52) ==15377== $
这是源(剪辑)：
for (i = 0; i < argc; i++) {
puts(argv[i]);
}
while ((c = getopt(argc,argv,"p")) != -1) {
switch (c) {
case 'p':
puts("FLAGON");
mkparents = true;
break;
case '?':
fprintf(stderr,"invalid option -- %c",optopt);
ret = 127;
goto end;
break;
}
}
所以它第一次运行它(mkdir -p)识别它(-p),第二次运行它,它没有.有任何想法吗？
解决方法
如果要扫描多个矢量,则需要通过将optind设置为1来重置getopt.
The variable optind is the index of the next element of the argv[]
vector to be processed. It shall be initialized to 1 by the system,
and getopt() shall update it when it finishes with each element of
argv[].
如果将optind设置为1不起作用,也请尝试0,我想我记得在某处阅读过.