Commands by pooderbill (4)

  • Useful for finding newly added lines to a file, tail + can be used to show only the lines starting at some offset. A syslog scanner would look at the file for the first time, then record the end_of_file record number using wc -l. Later (hours, days), scan only at the lines that were added since the last scan. Show Sample Output


    1
    tail +### MYFILE
    pooderbill · 2015-04-23 11:49:15 14
  • view is the command: vi -r which opens a file in read-only mode. The + character jumps to the bottom of the logfile where the most relevant information starts. Other aliases can be created for commonly viewed logfiles. Show Sample Output


    -1
    view + LOGFILE
    pooderbill · 2015-04-21 11:23:01 12
  • ps and grep is a dangerous combination -- grep tries to match everything on each line (thus the all too common: grep -v grep hack). ps -C doesn't use grep, it uses the process table for an exact match. Thus, you'll get an accurate list with: ps -fC sh rather finding every process with sh somewhere on the line. Show Sample Output


    14
    ps -fC PROCESSNAME
    pooderbill · 2015-04-20 13:09:44 17
  • The shortest and most complete comment/blank line remover... Any line where the first non-whitespace character is # (ie, indented # comments), and all null and blank lines are removed. Use the alias as a filter: noc /etc/hosts or grep server /etc/hosts | noc Change to nawk depending awk versions. Show Sample Output


    1
    alias noc="awk 'NF && ! /^[[:space:]]*#/'"
    pooderbill · 2014-09-07 00:50:57 72

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