Linux Interview Questions

Linux Interview Questions

What is awk?

awk (also written as Awk and AWK) is a utility that enables a programmer to write tiny but effective programs in the form of statements that define text patterns that are to be searched for in each line of a document and the action that is to be taken when a match is found within a line.

What is SED?

sed is a stream editor. A stream editor is used to perform basic text transformations on an input stream (a file, or input from a pipeline). ... But it is sed's ability to filter text in a pipeline which particularly distinguishes it from other types of editors.

A Stream EDitor is used to perform basic transformations on text read from a file or a pipe. The result is sent to standard output. The syntax for the sed command has no output file specification, but results can be saved to a file using output redirection.

What is the use of cat command in Unix?

UNIX Basic commands: cat. The cat command reads one or more files and prints them to standard output. The operator > can be used to combine multiple files into one. The operator >> can be used to append to an existing file.

#cat proc/cpuinfo //gives the cpu info or  

#dmidecode also gives the cpu info

#cat proc/meminfo //gives the mem info

What is the grep?

grep is a command-line utility for searching plain-text data sets for lines matching a regular expression. Its name comes from the ed command g/re/p (globally search a regular expression and print), which has the same effect: doing a global search with the regular expression and printing all matching lines.

Diff between find and grep?

grep is used to search for string in a file
find is used to searche files or directories