1、head - output the first part of files
head [OPTION]... [FILE]...
2、option
① -c, --bytes=[-]N:print the first N bytes of each file;
② -n, --lines=[-]N:print the first N lines instead of the first 10; with the leading '-', print all but the last N lines of each file
③ -q, never print headers giving file names
④ -v,always print headers giving file names
参考