ebcdic

contains hidden files, and the disk usage of subdirectories and files (sorted from large to small ): $ du -sk .[!.]* *｜ sort -nr Displays the directory size and total size with a depth of 1. $ du -d 1 -c -h Dd commandDd is a command on UNIx and Unix-like systems. Its main function is to convert and copy files.On Unix, Hardware Device Drivers (such as hard disks) and special device files (such as/dev/zero and/dev/urandom) appear in file systems like normal files; as long as the corresponding f

supports multiple character encoding (three, single-byte/variable-width multi-byte and General) single-byte character set-7-8-bit multi-Byte Character Set, including the Unicode Character Set is selected when the database is created, after selecting a character set, it is difficult to change it. In general, Unicode is recommended, because it is the most flexible character set, the 7-bit character set, the 7-bit American Information Interchange Standard Code (ASCII) (US7ASCII) 8-bit character se

: Transmission port and receiving port. It is mainly used to initiate a session or accept a session request between your systems (devices need to know each other, either an IP address, a MAC address, or a host name ). 6. Presentation Layer: ensure that the information sent by the application layer of one system can be read by the application layer of another system. For example, a PC program communicates with another computer. Does one computer use an extended Gbit/s exchange (

Windows Programming _ chap02_unicode _ Study Notes --By: neicole (2013.05.24) 01. Opening Chapter 1 of "windows program design" briefly describes the historical origins of Unicode (books are good, not boring at all, and look more like stories ), and the basic knowledge and application of wide characters in the C language in Windows programming. The book is simple and easy to learn. However, in conclusion, I feel that this chapter is not as easy as I think. How to organize them into knowledge mo

disabled while the other side is writing data to it, an error code is returned.World Language (the language of communication is very important)Now you can contact the machine, but be careful with what you said. Many machines have their own dialects, such as ASCII and ebcdic. The more common problem is the byte order. Unless you have always transmitted text, you must pay attention to this problem. Fortunately, people have found a solution.Long ago, pe

the most important character set in use today, despite its limitation to very few characters, because its design is the foundation for most modern character sets. ASCII provides only 128 numeric values, and 33 of those are reserved for special functions. The ebcdic (Extended Binary-coded decimal interchange code) Character Set and a number of associated character sets, designed by IBM (R) for its mainframes, uses 8-bit bytes. it was developed at a si

Od The OD (octal dump) filter will convert the input (or file) to octal or other hexadecimal. You need to view This command is useful when processing binary data files or an unreadable system device file, For example,/dev/urandom, or a binary data filter. DdThis is also a well-known tool, but it is a frightening "Data Replication" command.It is used to exchange data between a Unix microcomputer and an IBM mainframe through tape. This command still has itsThe purpose of the. dd command is simply

-N,--netmask -r,--reversed -Z,--silent #不进行arp毒化和主机扫描 -P,--Nopromisc -S,--nosslmitm #不使用ssl中间人攻击 -T,--proto #协议, Tcp/udp/all, default to All -U,--unoffensive -j,--load-hosts #加载保存的主机地址 -K,--save-hosts #保存扫描到的主机地址 -P,--plugin #载入插件 -F,--filter #载入过滤器文件 -A,--config #载入并使用一个非默认配置文件 --certificate #ssl攻击使用指定的证书文件 --private-key #ssl攻击使用指定的私钥文件 -W,--wifi-key #载入wifi密码: --wifi-key Wep:128:p:secret --wifi-key wep:128:s:ettercapwep0 --wifi-key ' wep:64

begins.Note: Usually only works when the output file is a disk or tape, that is, when backing up to disk or tape.Count=blocks: Copies only blocks blocks, the block size equals the number of bytes specified by IBS.Conv=conversion: Transforms the file with the specified parameters.ASCII: convert EBCDIC to ASCIIEBCDIC: convert ASCII to EBCDICIBM: Convert ASCII to alternate EBCDICBlock: Converts each row to a CBS length, with less space paddingUnblock: M

uses keys to authenticate files or messages between the system or the user.An HMAC (key hashing method for message authentication) is an example of this function. CRC (Cyclic redundancy Check): Cyclic redundancy check code, CRC verification due to simple implementation, the ability to detect errors, is widely used in various data validation applications. Less system resources, hardware and software can be achieved, is a data transmission error detection is a good means (CRC is not strictly a h

differs from cp . Before mentioning a very important point about Linux, everything is files , on Linux, hardware device drivers (such as hard disk) and special device files (such as /dev/zero and /dev/random ) are like ordinary files, as long as the respective drivers to achieve the corresponding function, DD You can also read from and/or write to these files. This dd can also be used in tasks such as backing up the boot sector of the hardware, obtaining a certain amount of random data, or empt

communicate when establishing a connection to a particular host or service.application Programming Interface : Now the common programming interface has sockets and Tli. And the front is sometimes called the "Berkeley socket", can be seen Berkeley for the development of the network of how much contribution.The OSI System Reference model and the TCP/IP system comparison: OSI seven-layer model TCP/IP four layer model Corresponding network protocol Application

ManagementCreate a virtual diskIntroduction to the DD command (partly explained from the DD (Unix) wiki))ddcommand is used to convert and copy files, but its replication differs from cp . Before mentioning a very important point about Linux, everything is files , on Linux, hardware device drivers (such as hard disk) and special device files (such as /dev/zero and /dev/random ) are like ordinary files, as long as the respective drivers to achieve the corresponding function, DD You can also read

process between hosts, which is responsible for establishing, managing, and terminating sessions between processes. The session layer also uses the insertion of checkpoints in the data to synchronize data. Typical protocol representatives: RPC, SQL, NFS, NetBIOS, SCP, ASP, SSH, Winsock, BSD sockets presentation Layer (Presentation) : Transforms the upper data or information to ensure that one host application layer information can be understood by another host's application. The data transfor

has constants and variable data types, including Boolean, reference types, composite types (records), and user-defined types Character data type Character data types store characters as strings and commonly used character data types are VARCHAR2 The bytes associated with the character are encoded in the schema, often called the character set and the code page. For example 7-bit ASCII, EBCDIC, and Unicode UTF-8 The length s

=clock ();if ((Cur-begin) >=10000){Lr_error_message ("Receive timeout, receive wait time =%d milliseconds", cur-begin);return ERROR;}ContinueDefaultLr_error_message ("recv Receive data error, error code:%d", ret);return ERROR;}//end switch}//end whilereturn SUCCESS;}Head * PHEAD=0;Connect * PCONNECT=0;Char csendbuf[4096];Char crecvbuf[4096];Pswrbuffer recvbuf=0;Vuser_init (){int ret=0;Lrs_set_recv_timeout (100,0);Lrs_set_recv_timeout2 (0,10);Lrs_startup (257);Create socketCreate_socket ();return

characters into two parts, which takes up to 6 characters in length. Therefore, if you need to support additional characters, it is recommended that you switch the character set of the database to the new Al32utf8.The UTF8 can be used in the database character set and also in the national character set.UtfeUTFE is a Unicode character set based on the EBCDIC platform, just like UTF8 on an ASCII platform. The difference is that, in Utfe, each character

Code originThe growth of the coding witnessed the computer by the individual to the collective by the State to the worldFirst, the initial codeThe computer originally coded the concept of the first computer everyone held 0101Second, the following is the origin of the byte"The so-called byte, the original meaning is used to denote a complete character." The initial computer performance and storage capacity are poor, so the general use of 4-bit BCD code (this code appears earlier than the computer

, EBCDIC, or GB2312; Consists of records (typically one record per line); Each record is delimited by a delimiter as a field (a typical delimiter has commas, semicolons, or tabs; sometimes separators can include optional spaces); Each record has the same field sequence. There are many CSV variants under these regular constraints, so CSV files are not completely interoperable. However, these mutations are very small and there are many appl

',' windows-1254 ',' windows-1255 ',' Windows-1256 ',' windows-1257 ',' windows-1258 ',' Johab ',' Macintosh ',' X-mac-japanese ',' X-mac-chinesetrad ',' X-mac-korean ',' X-mac-arabic ',' X-mac-hebrew ',' X-mac-greek ',' X-mac-cyrillic ',' X-mac-chinesesimp ',' X-mac-romanian ',' X-mac-ukrainian ',' X-mac-thai ',' X-mac-ce ',' X-mac-icelandic ',' X-mac-turkish ',' X-mac-croatian ',' X-chinese-cns ',' X-cp20001 ',' X-chinese-eten ',' X-cp20003 ',' x-cp20004 ',' X-cp20005 ',' X-ia5 ',' X-ia5-germ