unix shell command 'sed'

Usage: sed [OPTION]... {script-only-if-no-other-script} [input-file]...

  -n, --quiet, --silent
                 suppress automatic printing of pattern space
  -e script, --expression=script
                 add the script to the commands to be executed
  -f script-file, --file=script-file
                 add the contents of script-file to the commands to be executed
  -i[SUFFIX], --in-place[=SUFFIX]
                 edit files in place (makes backup if extension supplied)
  -l N, --line-length=N
                 specify the desired line-wrap length for the `l' command
  --posix
                 disable all GNU extensions.
  -r, --regexp-extended
                 use extended regular expressions in the script.
  -s, --separate
                 consider files as separate rather than as a single continuous
                 long stream.
  -b, --binary
                 do not convert DOS to UNIX lineendings (only on systems
                 supporting different lineendings).
  -u, --unbuffered
                 load minimal amounts of data from the input files and flush
                 the output buffers more often
      --help     display this help and exit
      --version  output version information and exit

If no -e, --expression, -f, or --file option is given, then the first
non-option argument is taken as the sed script to interpret.  All
remaining arguments are names of input files; if no input files are
specified, then the standard input is read.


practice
줄바꿈의 '\r' 문자 제거하여 다른 이름으로 저장
$ sed -e "s/\r$//" inputfile > newfile

"s/\r$//"
s: substitute (바꾸기)
/: delimiter (구분자)
\r$: 바꿀 문자(열), 여기서는 줄 끝($: end of line)에 오는 \r 문자를 바꿈
마지막 두 개의 delimiter 사이에는 아무 것도 주지 않음으로써 원하는 문자를 제거