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); } |
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); } |
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); } |
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); } |