以前測試時使用的 Linux 都是 CentOS，但是 CentOS 被 Red Hat 殺死後，今天想改用 RHEL8，結果，在安裝任何套件時都會出現
No match for argument: 套件名稱 的錯誤訊息，像是安裝 OpenJDK 11 會出現如下錯誤 …
No match for argument: java-11-openjdk No match for argument: java-11-openjdk-devel
後來發現是要先向 Red Hat 訂閱 repository，才可以拿到這些套件 …
sudo subscription-manager register --username=steventw --password=xxxxxxxx sudo subscription-manager attach --auto
sudo apt install net-tools sudo apt-get install pppoeconf
sudo pppoeconf除了帳號、密碼外，每個選項都用預設值，直接按【ENTER】，帳號的部份要特別注意，中華電信給的帳號可能為 74669091，在這裡要輸入 74669091@ip.hinet.net。
sudo pon dsl-provider
sudo poff -a
auth required pam_wheel.so trust group=wheel
auth required pam_wheel.so use_uid
usermod -a -G wheel user1 usermod -a -G wheel user2
yum update
yum install docker
OPTIONS='-s devicemapper --storage-opt dm.fs=xfs --exec-opt native.cgroupdriver=cgroupfs'
systemctl restart docker.service
systemctl enable docker.service
docker run dockerinaction/hello-world
yum remove docker
[steven@localhost ~]$ lsb_release -a LSB Version: :core-4.1-amd64:core-4.1-noarch:cxx-4.1-amd64:cxx-4.1-noarch:desktop-4.1-amd64:desktop-4.1-noarch:languages-4.1-amd64:languages-4.1-noarch:printing-4.1-amd64:printing-4.1-noarch Distributor ID: Scientific Description: Scientific Linux release 7.3 (Nitrogen) Release: 7.3 Codename: Nitrogen
[steven@localhost ~]$ uname -a
Linux localhost.localdomain 3.10.0-693.1.1.el7.x86_64 #1 SMP Tue Aug 15 08:36:44 CDT 2017 x86_64 x86_64 x86_64 GNU/Linux
| 項目 | 日期 | |
|---|---|---|
| * |
Environment
| |
| 1 | scientific linux 6.x 下如何播放音樂和影片? |
2014/07/27
|
| 2 | 在 scientific linux 上安裝 telnet & ssh service |
2014/12/21
|
| 3 | 在 ubuntu 上安裝 telnet service |
2014/12/29
|
| 4 | Ubuntu 上的 PPPoE 設定 |
2020/05/01
|
| 5 | install GlassFish Server |
2015/06/22
|
| 6 | 第一次使用 MySQL |
2014/10/10
|
| 7 | ssh 公鑰認證登入 |
2015/02/16
|
| 8 | 在 linux 中無法切換身份? (su: Permission denied) |
2017/12/22
|
| 9 | install Redis |
2018/07/21
|
| 10 | RHEL8 無法安裝套件 No match for argument: xxx |
2022/03/27
|
| 11 | install nfs server@Ubuntu |
2023/11/08
|
| * |
Shell Scripting
| |
| 1 | 使用 sort、join 處理 csv 檔案 |
2015/01/16
|
| 2 | EBCDIC <=> ASCII 間的轉換 |
2015/01/17
|
| * |
C Programming
| |
| 1 | 在 linux 下寫 C 程式 (使用 eclipse/CDT) |
2015/05/21
|
| 2 | Linux Network Programming - 初體驗 |
2015/05/23
|
| 3 | byte ordering functions |
2015/05/26
|
| 4 | fork Function |
2015/06/06
|
1 package idv.steven.nio2.filedir; 2 3 import static java.lang.System.out; 4 import java.nio.file.FileSystems; 5 import java.nio.file.Path; 6 import java.util.ArrayList; 7 8 public class ListRoots { 9 10 public static void main(String[] args) { 11 Iterable<Path> dirs = FileSystems.getDefault().getRootDirectories(); 12 13 ArrayList<Path> list = new ArrayList<Path>(); 14 for(Path name : dirs) { 15 list.add(name); 16 } 17 Path[] array = new Path[list.size()]; 18 list.toArray(array); 19 20 for(Path path : array) { 21 System.out.println(path); 22 } 23 24 //dirs.forEach(out::println); //Java 8 25 } 26 }
C:\
D:\
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F:\
H:\
1 package idv.steven.nio2.filedir; 2 3 import java.nio.file.FileSystems; 4 import java.nio.file.Files; 5 import java.nio.file.LinkOption; 6 import java.nio.file.Path; 7 8 public class CheckExist { 9 public static void main(String[] args) { 10 Path path = FileSystems.getDefault().getPath("D:/TEST"); 11 boolean isNotExist = Files.notExists(path, new LinkOption[] {LinkOption.NOFOLLOW_LINKS}); 12 System.out.println(isNotExist); 13 } 14 }
1 package idv.steven.nio2.filedir; 2 3 import java.io.IOException; 4 import java.nio.file.DirectoryStream; 5 import java.nio.file.Files; 6 import java.nio.file.Path; 7 import java.nio.file.Paths; 8 9 public class ListDirectory { 10 11 public static void main(String[] args) { 12 Path path = Paths.get("/home/steven/TEST"); 13 try (DirectoryStream<Path> ds = Files.newDirectoryStream(path, "[rR]eadme*.txt")) { 14 for(Path file : ds) { 15 System.out.println(file.getFileName()); 16 } 17 } 18 catch (IOException e) { 19 System.err.println(e); 20 } 21 } 22 }
1 package idv.steven.nio2.filedir; 2 3 import java.io.IOException; 4 import java.nio.file.FileVisitResult; 5 import java.nio.file.FileVisitor; 6 import java.nio.file.Files; 7 import java.nio.file.Path; 8 import java.nio.file.Paths; 9 import java.nio.file.attribute.BasicFileAttributes; 10 import static java.nio.file.FileVisitResult.*; 11 12 public class WalkFolder implements FileVisitor<Path> { 13 14 @Override 15 public FileVisitResult preVisitDirectory(Path dir, BasicFileAttributes attrs) 16 throws IOException { 17 18 System.out.println("preVisitDirectory: " + dir.getFileName()); 19 20 return CONTINUE; 21 } 22 23 @Override 24 public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) 25 throws IOException { 26 27 System.out.println("visitFile: " + file.getFileName()); 28 29 return CONTINUE; 30 } 31 32 @Override 33 public FileVisitResult visitFileFailed(Path file, IOException exc) 34 throws IOException { 35 36 System.out.println("visitFileFailed: " + file.getFileName()); 37 38 return CONTINUE; 39 } 40 41 @Override 42 public FileVisitResult postVisitDirectory(Path dir, IOException exc) 43 throws IOException { 44 45 System.out.println("postVisitDirectory: " + dir.getFileName()); 46 47 return CONTINUE; 48 } 49 50 public static void main(String[] args) throws IOException { 51 WalkFolder walkFolder = new WalkFolder(); 52 53 Files.walkFileTree(Paths.get("D:/TEST"), walkFolder); 54 } 55 }
1 package idv.steven.nio2.action; 2 3 import java.io.IOException; 4 import java.nio.file.Files; 5 import java.nio.file.Path; 6 import java.nio.file.Paths; 7 8 public class Copy { 9 10 public static void main(String[] args) throws IOException { 11 Path from = Paths.get("D:/TEST/readme.txt"); 12 Path to = Paths.get("D:/readme.txt"); 13 Files.copy(from, to); 14 } 15 }
import static java.nio.file.StandardCopyOption.*; import static java.nio.file.LinkOption.*; … Files.copy(from, to, REPLACE_EXISTING, COPY_ATTRIBUTES, NOFOLLOW_LINKS);
1 package idv.steven.nio2.metadata; 2 3 import java.io.IOException; 4 import java.nio.file.Files; 5 import java.nio.file.Path; 6 import java.nio.file.Paths; 7 import java.nio.file.attribute.GroupPrincipal; 8 import java.nio.file.attribute.PosixFileAttributeView; 9 import java.nio.file.attribute.PosixFileAttributes; 10 import java.nio.file.attribute.PosixFilePermission; 11 import java.nio.file.attribute.PosixFilePermissions; 12 import static java.nio.file.LinkOption.NOFOLLOW_LINKS; 13 import java.util.Set; 14 15 public class POSIXView { 16 17 public static void main(String[] args) { 18 PosixFileAttributes attr = null; 19 Path path = Paths.get("/home/steven/seal/steven.pub"); 20 21 // read permissions 22 try { 23 attr = Files.readAttributes(path, PosixFileAttributes.class); 24 } catch (IOException e) { 25 System.err.println(e.getMessage()); 26 } 27 28 System.out.println("File owner: " + attr.owner().getName()); 29 System.out.println("File group: " + attr.group().getName()); 30 System.out.println("File permissions: " + attr.permissions().toString()); 31 32 // set permissions 33 Set<PosixFilePermission> permissions = PosixFilePermissions.fromString("rw-r--r--"); 34 try { 35 Files.setPosixFilePermissions(path, permissions); 36 37 GroupPrincipal group = path.getFileSystem(). 38 getUserPrincipalLookupService().lookupPrincipalByGroupName("steven"); 39 Files.getFileAttributeView(path, PosixFileAttributeView.class).setGroup(group); 40 41 GroupPrincipal groupSteven = (GroupPrincipal) Files.getAttribute(path, "posix:group", NOFOLLOW_LINKS); 42 System.out.println(group.getName()); 43 } catch (IOException e) { 44 System.err.println(e); 45 } 46 } 47 }
File owner: steven File group: steven File permissions: [OTHERS_READ, OWNER_WRITE, GROUP_WRITE, OWNER_READ, GROUP_READ]
Path newFolder = FileSystems.getDefault().getPath("/home/steven/newFolder");
Set<PosixFilePermission> perms = PosixFilePermissions.fromString("rwxr-x---");
FileAttribute<Set<PosixFilePermission>> attr = PosixFilePermissions.asFileAttribute(perms);
try {
Files.createDirectory(newFolder, attr);
} catch (IOException e) {
System.err.println(e);
}
2 #include <unistd.h> 3 4 int globvar = 6; 5 char buf[] = "a write to stdout\n"; 6 7 int main(void) { 8 int var; 9 pid_t pid; 10 11 var = 88; 12 if (write(STDOUT_FILENO, buf, sizeof(buf)-1) != sizeof(buf)-1) 13 printf("write error"); 14 printf("before fork\n"); 15 16 if ((pid = fork()) < 0) { 17 printf("fork error"); 18 } 19 else if (pid == 0) { 20 globvar++; 21 var++; 22 } 23 else { 24 sleep(2); 25 } 26 27 printf("pid = %ld, getpid = %ld, glob = %d, var = %d\n", (long) pid, (long) getpid(), globvar, var); 28 _exit(0); 29 }上面的程式很簡單的利用 fork 產生一個子行程，等待 2 秒後，印出一段訊息，顯示 fork 傳回值、行程的 pid (process id)、全域變數及區域變數，執行結果如下: (我的程式命名為 forEx01.c)
[steven@CentOS7 Debug]$ ./forkEx01
a write to stdout
before fork
pid = 0, getpid = 9214, glob = 7, var = 89
pid = 9214, getpid = 9213, glob = 6, var = 88
[steven@CentOS7 Debug]$
1 #include <sys/socket.h> 2 #include <sys/types.h> 3 #include <stdio.h> 4 #include <unistd.h> 5 #include <netinet/in.h> 6 #include <string.h> 7 #include <arpa/inet.h> 8 #include <time.h> 9 10 const int MAXLINE = 100; 11 const int LISTENQ = 1024; 12 13 int main(int argc, char **argv) { 14 int listenfd, connfd; 15 struct sockaddr_in servaddr; 16 char buff[MAXLINE]; 17 18 time_t ticks; 19 listenfd = socket(AF_INET, SOCK_STREAM, 0); 20 21 bzero(&servaddr, sizeof(servaddr)); 22 servaddr.sin_family = AF_INET; 23 servaddr.sin_addr.s_addr = htonl(INADDR_ANY); 24 servaddr.sin_port = htons(1513); 25 26 bind(listenfd, (struct sockaddr *) &servaddr, sizeof(servaddr)); 27 listen(listenfd, LISTENQ); 28 29 for( ; ; ) { 30 connfd = accept(listenfd, (struct sockaddr *) NULL, NULL); 31 32 ticks = time(NULL); 33 snprintf(buff, sizeof(buff), "%.24s\r\n", ctime(&ticks)); 34 write(connfd, buff, strlen(buff)); 35 36 close(connfd); 37 } 38 39 }
1 #include <stdio.h> 2 #include <sys/socket.h> 3 #include <sys/types.h> 4 #include <netinet/in.h> 5 #include <strings.h> 6 #include <arpa/inet.h> 7 8 const int MAXLINE = 100; 9 10 void err_sys(const char* x, ...) 11 { 12 perror(x); 13 //exit(1); 14 } 15 16 void err_quit(const char* x, ...) 17 { 18 perror(x); 19 //exit(1); 20 } 21 22 int main(int argc, char **argv) 23 { 24 int sockfd, n; 25 char recvline[MAXLINE + 1]; 26 struct sockaddr_in servaddr; 27 28 if (argc != 2) { 29 err_quit("usage: a.out <IPaddress>"); 30 return 1; 31 } 32 33 if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0) { 34 err_sys("socket error"); 35 return 1; 36 } 37 38 bzero(&servaddr, sizeof(servaddr)); 39 servaddr.sin_family = AF_INET; 40 servaddr.sin_port = htons(1513); 41 if (inet_pton(AF_INET, argv[1], &servaddr.sin_addr) <= 0) 42 err_quit("inet_pton error for %s", argv[1]); 43 44 if (connect(sockfd, (struct sockaddr *) &servaddr, sizeof(servaddr)) < 0) 45 err_sys("connect error"); 46 47 while ((n = read(sockfd, recvline, MAXLINE)) > 0) { 48 recvline[n] = 0; 49 if (fputs(recvline, stdout) == EOF) 50 err_sys("fputs error"); 51 } 52 53 if (n < 0) { 54 err_sys("read error"); 55 return 1; 56 } 57 58 return 0; 59 }
