1、定制自己的ls命令
#include <stdio.h>
#include <sys/types.h>
#include <dirent.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <string.h>
#include <sys/types.h>
#include <pwd.h>
#include <grp.h>
#include <time.h>
void do_ls(char*dir_entry);
void do_ls_filename(char*dir_entry);
void do_stat( char* filename );
void show_list( char* filename, struct stat* statinfo );
void mode_to_letters( mode_t filemode, char str[] );
void show_time( time_t filetime );
char* format_time( char* dsttime, const char* srctime );
//用户id转名称
char* uid_to_name( uid_t uid );
//组id转名称
char* gid_to_name( gid_t gid );
int flag;
int main(int argc,char*argv[])
{
char*dir=".";
if(argc>2)
{
dir=argv[3];
}
//printf("%s\n",dir );
//printf("%c\n",argv[2][1] );
switch(argv[2][1]){
case 'l':flag=0;do_ls(argv[3]);break;
case 'A':flag=1;do_ls(argv[3]);break;
case 'n':flag=2;do_ls(argv[3]);break;
case 'a':flag=3;do_ls(argv[3]);break;
case 'm':flag=4;do_ls(argv[3]);break;
}
}
void do_ls(char* dir_entry) {
DIR* pDir;
struct dirent* pCurDir;
if( ( pDir = opendir( dir_entry ) ) == NULL ){
perror( "read dir" );
exit( -1 );
}
else {
while( ( pCurDir = readdir( pDir ) ) != NULL ) {
//printf("%s\n",pCurDir->d_name );
do_stat( pCurDir->d_name );
}
closedir( pDir );
}
}
//得到文件信息
void do_stat( char* filename ){
struct stat statinfo;
if ( stat( filename, &statinfo ) == -1 ) {
printf( "打开%s失败\n", filename );
exit( -1 );
}else {
show_list( filename, &statinfo );
}
}
//显示文件列表
void show_list( char* filename, struct stat* statinfo ) {
mode_t st_mode = statinfo->st_mode;
char str[10];
mode_to_letters( st_mode, str );
switch(flag){
case 0:{
printf( "%s\t", str ); //文件权限和文件类型信息
printf( "%ld\t", statinfo->st_nlink ); //该文件上硬链接个数
printf( "%s\t\t", uid_to_name( statinfo->st_uid ) ); //UID号转用户名
printf( "%s\t", gid_to_name( statinfo->st_gid ) ); //GID号转组名
printf( "%10ld", statinfo->st_size ); //文件大小
show_time( statinfo->st_mtime ); //最后一次修改时间
printf( "\t%s", filename );
printf( "\n" );
};break;
case 1:{
printf("%s ",filename );
};break;
case 2:{
printf( "%s\t", str ); //文件权限和文件类型信息
printf( "%ld\t", statinfo->st_nlink ); //该文件上硬链接个数
printf( "%d\t\t", statinfo->st_uid ); //UID号
printf( "%d\t", statinfo->st_gid ); //GID号
printf( "%10ld", statinfo->st_size ); //文件大小
show_time( statinfo->st_mtime ); //最后一次修改时间
printf( "\t%s", filename );
printf( "\n" );
};break;
case 3:
printf("%s ", filename);break;
case 4:
printf("%s,",filename);break;
}
printf("\n");
}
char* uid_to_name( uid_t uid ){
return getpwuid( uid )->pw_name;
}
char* gid_to_name( gid_t gid ){
return getgrgid( gid )->gr_name;
}
void mode_to_letters( mode_t filemode, char str[] ) {
strcpy( str, "----------" );
if( S_ISREG( filemode ) ) str[0] = '-';
if( S_ISDIR( filemode ) ) str[0] = 'd';
if( S_ISLNK( filemode ) ) str[0] = 'l';
//用户权限位
if( filemode & S_IRUSR ) str[1] = 'r';
if( filemode & S_IWUSR ) str[2] = 'w';
if( filemode & S_IXUSR ) str[3] = 'x';
//组权限位
if( filemode & S_IRGRP ) str[4] = 'r';
if( filemode & S_IWGRP ) str[5] = 'w';
if( filemode & S_IXGRP ) str[6] = 'x';
//其他组权限位
if( filemode & S_IROTH ) str[7] = 'r';
if( filemode & S_IWOTH ) str[8] = 'w';
if( filemode & S_IXOTH ) str[9] = 'x';
}
void show_time( time_t filetime ) {
struct tm* ptm;
ptm = localtime( &filetime );
int month = ptm->tm_mon + 1;
int day = ptm->tm_mday;
int hour = ptm->tm_hour;
int min = ptm->tm_min;
char srchour[3] = "0";
char srcmin[3] = "0";
char dsthour[3] = "0";
char dstmin[3] = "0";
sprintf( srchour, "%d", hour );
sprintf( srcmin, "%d", min );
format_time( dsthour, srchour );
format_time( dstmin, srcmin );
printf( "%4d月%4d%4s:%2s", month, day, dsthour, dstmin );
}
char* format_time( char* dsttime, const char* srctime ) {
if( strlen( srctime ) < 2 ) {
return strcat( dsttime, srctime );
}
return strcpy( dsttime, srctime );
}
2、遍历当前目录,输出目录和文件详细信息
#include <unistd.h>
#include <stdio.h>
#include <string.h>
#include <dirent.h>
#include <sys/stat.h>
#include <stdlib.h>
#define MAX 102
void printdir(char*dir,int depth)
{
DIR *dp;
struct dirent *entry;
struct stat statbuf;
if((dp=opendir(dir))==NULL)
{
//fprintf(stderr,"can't not open directory:%s\n",dir);
return;
}
chdir(dir);
while((entry=readdir(dp)) != NULL)
{
lstat(entry->d_name,&statbuf);
if(S_ISDIR(statbuf.st_mode))
{
if(strcmp(".",entry->d_name)==0||strcmp("..",entry->d_name)==0)
continue;
printf("%*s%s/\n",depth,"",entry->d_name);
printdir(entry->d_name,depth+4);
}
else
printf("%*s%s\n",depth,"",entry->d_name);
}
closedir(dp);
}
int main()
{
char buffer[MAX];
char *p=getcwd(buffer,MAX);
printf("The current directory:%s\n",buffer);
printdir(buffer,0);
return 0;
}