展示目录的小程序
展示指定目录的小程序：
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#include <unistd.h>
#include <stdio.h>
#include <dirent.h>
#include <string.h>
#include <sys/stat.h>
#include <stdlib.h>
void printdir(char *dir,int depth){
DIR *dp;
struct dirent *entry;
struct stat statbuf;
if((dp = opendir(dir)) == NULL){
fprintf(stderr, "cannot open directory: %s\n", dir);
return;
}
chdir(dir);
while((entry = readdir(dp)) != NULL){
lstat(entry->d_name,&statbuf);
if(S_ISDIR(statbuf.st_mode)){
/*Found a directory,but ignore . and ..*/
if(strcmp(".",entry->d_name) == 0 || strcmp("..",entry->d_name) == 0){
continue;
}
printf("%*s%s/ \n",depth,"",entry->d_name);
/*Recurse at a new indent level*/
printdir(entry->d_name,depth+4);
}else{
printf("%*s%s \n",depth,"",entry->d_name);
}
}
}
int main(){
/*
show directory
*/
printf("Directory scan of /home:\n");
printdir("/home",0);
printf("done. \n");
exit(0);
}
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根据参数输出目录的结构
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#include <unistd.h>
#include <stdio.h>
#include <dirent.h>
#include <string.h>
#include <sys/stat.h>
#include <stdlib.h>
void printdir(char *dir,int depth){
DIR *dp;
struct dirent *entry;
struct stat statbuf;
if((dp = opendir(dir)) == NULL){
fprintf(stderr, "cannot open directory: %s\n", dir);
return;
}
chdir(dir);
while((entry = readdir(dp)) != NULL){
lstat(entry->d_name,&statbuf);
if(S_ISDIR(statbuf.st_mode)){
/*Found a directory,but ignore . and ..*/
if(strcmp(".",entry->d_name) == 0 || strcmp("..",entry->d_name) == 0){
continue;
}
printf("%*s%s/ \n",depth,"",entry->d_name);
/*Recurse at a new indent level*/
printdir(entry->d_name,depth+4);
}else{
printf("%*s%s \n",depth,"",entry->d_name);
}
}
}
int main(int argc, char* argv[]){
/*
show directory
*/
char *topdir = ".";
if(argc >= 2){
topdir = argv[1];
}
printf("Directory scan of %s:\n",topdir);
printdir(topdir,0);
printf("done. \n");
exit(0);
}
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获取主机基本信息
获取主机用户信息:
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#include <sys/types.h>
#include <pwd.h>
#include <stdio.h>
#include <unistd.h>
int main(){
uid_t uid;
gid_t gid;
struct passwd *pw;
uid = getuid();
gid = getgid();
printf("User is %s\n",getlogin());
printf("User IDs: uid=%d, gid=%d \n", uid, gid);
pw = getpwuid(uid);
printf("UID passwd entry: \n name=%s, uid=%d, gid=%d, home=%s, shell=%s\n",pw->pw_name, pw->pw_uid, pw->pw_gid, pw->pw_dir, pw->pw_shell);
pw = getpwnam("root");
printf("root passwd entry: \n");
printf("name=%s, uid=%d, gid=%d, home=%s, shell=%s \n",pw->pw_name, pw->pw_uid, pw->pw_gid, pw->pw_dir, pw->pw_shell);
exit(0);
}
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获取主机自身信息:
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#include <sys/utsname.h>
#include <unistd.h>
#include <stdio.h>
int main(){
char computer[256];
struct utsname uts;
if(gethostname(computer, 255) != 0 || uname(&uts) < 0){
fprintf(stderr, "Could not get host information \n");
exit(1);
}
printf("Computer host name is %s \n",computer);
printf("System is %s on %s hardware \n",uts.sysname, uts.machine);
printf("Nodename is %s \n",uts.nodename);
printf("Version is %s , %s \n",uts.release, uts.version);
exit(0);
}
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