linux grep recursive

Have you ever had the need to calculate a very large data (several hundred GB? Or search in it, or other operations-some operations that cannot be performed in parallel. Data Experts, I am talking to you. You may have a 4-core or more multi-core CPU, but our appropriate tool, suchGrep,Bzip2,Wc,Awk,SedAnd so on. They are all single-threaded and can only use one CPU core."How can I use these kernels "?To allow Linux commands to use all the CPU cores, we

/M01/72/93/wKioL1XnKBDCWy-FAADVIQ4i-nw626.jpg "title=" V ' Dv465ebhrztfqx1tt{6gb.png "alt=" Wkiol1xnkbdcwy-faadviq4i-nw626.jpg "/>2. Display the two-digit or three-digit number in the/etc/passwd filegrep ' [0-9]\{2,3\} '/etc/passwd3. Display lines with ' LISTEN ' followed by 0, one or more whitespace characters in the ' Netstat-tan ' command result?4. Add user bash, Testbash, basher, and Nologin user (Nologin user's shell is/sbin/nologin), then find the same line in the/etc/passwd file as the us

Linux File Operations Command introduction1) grepgrep is used to find eligible records in a filegrep parameter Filter criteria fileRegular expressions can be used in filtered conditions-C Displays the number of rows that match-I ignores case-n displays records that meet the requirements, including line numbers-V displays records that do not meet the requirements-a n displays the records that meet the requirements, and the following n rows-B N Displays

the itineraryPid:pid%CPU: CPU Usage consumed%MEM: Usage of memory consumedVSZ: Virtual Memory size occupiedRSS: Size of memory consumedTTY: Secondary device number for the terminal (minor device numbers of TTY)STAT: The state of the tripStart: Trip start timeTime: When it was executedCommand: the command executedThere are 5 states of processes on Linux:1. Running (running or waiting in the running queue)2. Interrupt (dormant, blocked, waiting for

Popen is failed\n");Break ;}memset (castdoutline, 0, sizeof (castdoutline));while (NULL! = fgets (Castdoutline,sizeof (castdoutline),FP)){//split string with space separatorpctmp = strtok (Castdoutline, "");//user name skipped, direct matching PID, mismatched skippctmp = strtok (NULL, "");if (0! = strncasecmp (Caselfpid,Pctmp,strlen (caselfpid))) {continue;}//read out process itself CPU usagepctmp = strtok (NULL, "");printf ("CPU =%s%%\n", pctmp);//read out process self MEM occupancy ratepctmp

2. UseThe grep command in a Linux system is a powerful text search tool. This command is a global lookup regular expression and prints command line commands. grep consists of two egrep and grep.2. Formatgrep [Options] File3. Main parameters (Common) -E If this option is added, the extended regular is supported. Equival

The application of grep and regular expressionsLinux Text Processing Three musketeers:grep: text filtering tools;sed : Text editor (line); stream Editorawk : Text report Generator; awk implementation on Linux is Gawkgrep : Global search REgular expression and Print out Theline. Function: Text Search tool, according to user-specified "pattern" line to search for target text, print the matching line; patt

grep is the command of the Linux Chinese editing class to select the desired text contentMain format: grep [option] "PATTERN" FILENAMEOption:-I ignores case-O displays only the characters that match-V Reverse display (shows rows not matched to)--color to display matching characters in color notation"PATTERN": Supports RegExp (regular expression)1, character match

Today, Mayuyu Some of the commands that are commonly used in Linux.1. grep commandgrep is used to filter what you need, and the syntax is as followsgrep Mayuyu--colorFilters out all rows that contain Mayuyu, and grep also supports regular expressions.2. SED commandThere are two main issues when editing a file using the normal VIM editor (1) When the file is relat

Article Title: How to fix virus-infected Grep programs in Linux. Linux is a technology channel of the IT lab in China. Including desktop applications, Linux system management, kernel research, embedded systems, open-source, and other basic classification, General viruses will mainly infect executable files under/bin. 　

For shell, sed, grep, and regular expressions in LINUX, you must learn about the common Linux technology-Linux programming and kernel information. For more information, see the following. For example, for a person working in LINUX, shell, sed,

The grep command is all called Global search Regular expression (RE) and print out of the line, which is a comprehensive search for regular expressions and prints the lines. It can use regular expressions to search for text and print out matching rows.Grammar:grep [-ACINV] [--color=auto] ' search string ' file nameParameter explanation:-A: binary files are searched for data in the form of a text file-C: Calculates the number of times to find the ' pen

#This script is to parse data file:Fun0 (){##[INFO1]A=1 b=2 c=3[INFO2]A=7 b=8 c=9[INFO3]A=x b=y C=z}#! /bin/bashRead Info ABC#echo $InfoIf ["$Info"! = "INFO1"-a "$Info"! = "INFO2"-a "$Info"! = "INFO3"]Thenecho "Wrong info!"Exit 0FiSed '/^#\|^$/d ' | Grep-a1 "$Info" | Tail-1 | Awk-f ' [=]+ '-v var= "$ABC" ' {if (var==$1) {print $}else if (var==$3) {print $4}else if (var==$5) {print $6}else {print "Wrong abc!"}} '#some NOTES#awk ' BEGIN {fs= ' [=]+ '} {

Title: Use of the grep commandrole:grep can parse a line of text, get the keyword, if the row has a keyword, will be the whole row out.grep [-ACINV] [--color=auto] ' Find string ' filenameFirst, the parameters　　-A: binary files are searched for data in text mode-C: Calculates the number of rows found matching a string-I: Ignoring case differences, all case is considered the same-N: Output line number-O: Output only strings on matching-V: Reverse selec

grep :Searches for text based on pattern (mode) and displays lines of text that conform to the pattern, without modifying the original file.Usage: grep [options] ' pattern '/file #也可以利用管道进行匹配-I ignore ignoring case--colour the matched string with a color.-V reverse lookup, showing rows that do not match pattern-O displays only strings that are matched by the patternRegular Expressions REGular expressionWork

POSIX character entity: [: entity name:]: [: Alpha:], [: lower:], [: Upper:]: letter, lower case letter, upper case letter [: Digit:], [: xdigit:]: decimal number, hexadecimal number [: Alnum:]: letters, numbers [: Punct:]: punctuation [: Space:]: blank (space, tab, new line) [: Graph:]: printable character, non-control character, not including spaces! [: Print:]: printable character, non-control character, including space, [:], [:], [: Cntrl:]: Control Character Several mod

Reprint Link: http://www.eguidedog.net/linux-tutorial/05-grep.phpgrep is a command that is commonly used under the Linux command line to find the contents of a filtered text file. The simplest usage is: grep Apple Fruitlist.txt If you want to ignore case, you can use the-I parameter: grep-i Apple Fr

writing a wildcard scheme in a file, grep will not go to the file that matches the filename in the scheme to find the matching content--exclude-dir=dir matches a lot of content in a directory and also allows some subdirectories to not accept matches, use this optionGrep-h-R--exclude-dir=2* "old"./*-I.-r-r Recursive LookupOther options--mmap Enable MMAP system call instead of read system call-U default

grep commandPS commandThe PS command in Linux is the abbreviation for process status. The PS command is used to list those processes that are currently running on the system. The PS command lists the current snapshots of those processes, which are those that are executing the PS command at the moment, and if you want to display process information dynamically, you can use the top command. PS gives us a one-

GrepIntroductionOne of the Three Musketeers of the Linux text processing, the File filtering tool (the other two musketeers for sed: Text Editing Tool,awk: Text Report Generator) owned, according to user-specified "mode" Matches the target text line by row, and prints the function of the matching line. UseGrep can also use regular expression characters in addition to normal character usage. Important command options for