//调用
//char *ptr = (char *)malloc(sizeof(char) * 128);
//ptr = get_passwd();
//printf("\n");

#include<stdio.h>

#include<termios.h>

#include<unistd.h>

#include<assert.h>

#include<string.h>

#include <stdlib.h>

int getch()

{

int c=0;

struct termios org_opts, new_opts;

int res=0;

//-----  store old settings -----------

res=tcgetattr(STDIN_FILENO, &org_opts);

assert(res==0);

//---- set new terminal parms --------

memcpy(&new_opts, &org_opts, sizeof(new_opts));

new_opts.c_lflag &= ~(ICANON | ECHO | ECHOE | ECHOK | ECHONL | ECHOPRT | ECHOKE | ICRNL);

tcsetattr(STDIN_FILENO, TCSANOW, &new_opts);

c=getchar();

//------  restore old settings ---------

res=tcsetattr(STDIN_FILENO, TCSANOW, &org_opts);

assert(res==0);

return c;

}

char *get_passwd()

{

    int i;

    char *pd = (char *)malloc(sizeof(char) * 128);

    for(i = 0; ; i++)

    {

pd[i] = getch();

if(pd[i] == ‘\n‘)

{

   pd[i] = ‘\0‘;

   break;

}

if(pd[i] == 127)

{

   printf("\b \b");

   i = i - 2;

}

else

{

   printf("*");

}

if(i<0)

{

   pd[0]=‘\0‘;

}

    }

    return pd;

}