cat, grep, cut, sed and awk to get data about your system - Linux скачать в хорошем качестве

cat, grep, cut, sed and awk to get data about your system - Linux

Learn how to use cat, grep, cut, sed and awk to get data about your system. We will be trying to get the "Total usable memory" from the /proc/meminfo file just to demonstrate this. Here are the commands used in this video. cat /proc/meminfo cat /proc/meminfo | grep MemTotal cat /proc/meminfo | grep MemTotal | cut -d: -f 2 cat /proc/meminfo | grep MemTotal | cut -d: -f 2 | sed 's/^ *//g' ^ denotes that what appears after the ^ must appear at the beginning of the pattern space. $ is the same as ^, but refers to end of pattern space. $ also acts as a special character only at the end of the regular expression or subexpression (that is, before \) or \|), and its use at the end of a subexpression is not portable. means what matches a sequence of zero or more instances of matches for the preceding regular expression cat /proc/meminfo | grep MemTotal | cut -d: -f 2 | sed 's/^ *//g' | cut -d ' ' -f 1 cat /proc/meminfo | grep MemTotal | cut -d: -f 2 | sed 's/^ *//g' | cut -d ' ' -f 1 | awk '{print $0*1024}' cat /proc/meminfo | grep MemTotal | cut -d: -f 2 | sed 's/^ *//g' | cut -d ' ' -f 1 | awk '{print $0*1024" bytes"}' cat /proc/meminfo | grep MemTotal | cut -d: -f 2 | sed 's/^ *//g' | cut -d ' ' -f 1 | awk '{print $0*1024" bytes"}' abc.txt YOUTUBE #linux #ubuntu #bash #shell #script