Shell

Enter HBase Shell Console $HBASE _home/bin/hbase Shell If you have Kerberos authentication, you need to use the appropriate keytab for authentication (using the Kinit command), and then use the HBase shell after the authentication is successful. You

File expression-e filename true if filename exists-d filename If filename is a directory, true-F filename True if filename is a regular file-L filename True if filename is a symbolic link-r filename If filename is readable, true-W filename if

Definition and use of 1.shell variables my_dir= "/home/yk/desktop"　　 # ( any character in single quotation marks is output as is, the variable in the single-quote string is not valid;)Echo $my _direcho ${#my_dir} #获取字符串长度2.shell annotations　Single

DeclareSet - R Read-only 　　　　-I set shaping　　　　 -A array Let the specified function be an array 　　　　 -F function If used in a script without declare -f any

Shell IntroductionThe shell is a program written in C and a bridge for users to use Linux. The shell is both a command language and a programming language.Shell script, a scripting program written for the shell.Shell Environment The Bourne

I. Condition TEST ACTIONThe shell environment determines whether the execution succeeds based on the return status value ($?) after the command executes, or if the return value is 0 o'clock, which indicates a success or failure or exception. You can

# Experimental Case One,**Writing sysmon.sh Scripts(1) Use the DF command to extract the disk occupancy of the root partition and assign a value to the variable dug.(2) Use the Mpstat command to extract the CPU usage (Install the SYSSTAT package)

Shell Arrayshell支持一维数组（不支持多维数组），并且没有限定数组的大小。Defining arraysshell中，用括号来表示数组，数组元素用空格分隔，下标从0开始Mode 1 数组名=(值1 值2...值n)，如array_name=(value0 value1 value2)Mode 2 array_name=(value0 value1 value2 )Method 3 defines the value of the array

Implementation scenario: 1. Add:& at the end of the command#/bin/Bashall_num=Tena=$(Date+%h%m%S) forNuminch`seq 1${all_num} ' Do { Sleep 1 Echo${num}}& Doneb=$(Date+%h%m%S)Echo-E"starttime:\t$a"Echo-E"endtime:\t$b"With the & symbol at the end

I am used to the C/C ++ programming environment, and then switched to shell programming, there is always a strange feeling. The general if-then-else Function Format in shell is as follows: If condition 1 Then command 1 Elif condition 2

Why do we have to work overtime, not occasionally. If a large number of people work overtime due to our ability problems, we can only say that the HR department has recruited the wrong person. We should not come here to dismiss us. How many

-B. returns true if the file exists and is a block file. -C: returns true if the file exists and is a character file. -D. If pathname exists and is a directory, true is returned. -E: returns true if the file or directory specified by

Shelll basic programming theory and some examples   Abstract: This article describes how to compile a shell script based on a large number of instances. (13:27:24) Why shell programming? In Linux, although there are various graphical interface

0x00 Preface The first thing for shelling is to find the OEP (oringinal entry point). Because of shelling, when the PE file is loaded into OD or other debugging software, it is usually the entry address of the shell program. So the first step of

Problem: It is necessary to pre-process a file of several GB and tens of millions of lines. Function: splits records in a file into different files according to certain rules. Advantage: It is really convenient to use shell scripts for text

Shell Basics The first word entered in the command line must be the name of a command, and the second word is the option or parameter of the command. Each word in the command line must be separated by spaces or tabs. The format is as follows:$

Shell special characters Wildcard Wildcard characters are used for pattern matching, such as file name matching, path name searching, and string searching. Common wildcard characters include (*),(?) And the Character Sequence enclosed in square

Standard Input and Output When executing a shell command line, three standard documents (stdin) are automatically opened, which usually correspond to the keyboard of the terminal. stdout) and stderr correspond to the terminal screen. The process

Use VC # easily create SQL Shell (Author: mikespook | Release Date: 354-10-7 | views) Keywords: C #, database, extended stored procedure, Vulnerability This article has contributed to the hacker security base. The article is owned

I. Use of local variables Local variables act only in this shell, just like local variables. It does not affect variables in other shells. 1. Show variable valuesYou can use the echo command. Note that you must add the $ symbol before the variable