Commands tagged ps1 (7)

  • Run the alias command, then issue ps aux | head and resize your terminal window (putty/console/hyperterm/xterm/etc) then issue the same command and you'll understand. ${LINES:-`tput lines 2>/dev/null||echo -n 12`} Insructs the shell that if LINES is not set or null to use the output from `tput lines` ( ncurses based terminal access ) to get the number of lines in your terminal. But furthermore, in case that doesn't work either, it will default to using the deafault of 12 (-2 = 10). The default for HEAD is to output the first 10 lines, this alias changes the default to output the first x lines instead, where x is the number of lines currently displayed on your terminal - 2. The -2 is there so that the top line displayed is the command you ran that used HEAD, ie the prompt. Depending on whether your PS1 and/or PROMPT_COMMAND output more than 1 line (mine is 3) you will want to increase from -2. So with my prompt being the following, I need -7, or - 5 if I only want to display the commandline at the top. ( http://www.askapache.com/linux-unix/bash-power-prompt.html ) 275MB/748MB [7995:7993 - 0:186] 06:26:49 Thu Apr 08 [askapache@n1-backbone5:/dev/pts/0 +1] ~ In most shells the LINES variable is created automatically at login and updated when the terminal is resized (28 linux, 23/20 others for SIGWINCH) to contain the number of vertical lines that can fit in your terminal window. Because the alias doesn't hard-code the current LINES but relys on the $LINES variable, this is a dynamic alias that will always work on a tty device. Show Sample Output


    26
    alias head='head -n $((${LINES:-`tput lines 2>/dev/null||echo -n 12`} - 2))'
    AskApache · 2010-04-08 22:37:06 7
  • I use this command (PS1) to show a list bash prompt's special characters. I tested it against A flavor of Red Hat Linux and Mac OS X Show Sample Output


    3
    alias PS1="man bash | sed -n '/ASCII bell/,/end a sequence/p'"
    haivu · 2010-01-15 23:39:28 0
  • If the return code from the last command was greater than zero, colour part of your prompt red. The commands give a prompt like this: [user current_directory]$ After an error, the "[user" part is automatically coloured red. Tested using bash on xterm and terminal. Place in your .bashrc or .bash_profile.


    3
    export PROMPT_COMMAND='if (($? > 0)); then echo -ne "\033[1;31m"; fi'; export PS1='[\[\]\u\[\033[0m\] \[\033[1;34m\]\w\[\033[0m\]]\$ '
    quintic · 2010-08-25 21:19:30 0
  • blue and yellow colored bash prompt for a Hanukkah celebration on your box


    2
    export PS1="\e[0;34m[\u\e[0;34m@\h[\e[0;33m\w\e[0m\e[0m\e[0;34m]#\e[0m "
    decept · 2009-12-13 18:35:06 1
  • Adds the time in 12hr AM/PM format to the beginning of a prompt. Change \@ to \t for 24-hour time or \T for 12hr without AM/PM. To keep the time the next time you open a terminal, edit ~/.bashrc and stick the command at the bottom. Show Sample Output


    1
    export PS1="(\@) $PS1"
    cmdq · 2010-11-22 04:50:21 0
  • A simple PS1, ready to be used. Just paste in your ~/.bashrc Show Sample Output


    0
    export PS1="[\[\e[1;32m\]\u\[\e[m\]\[\e[1;31m\]@\[\e[m\]\[\e[3;35m\]\H\[\e[m\] \[\e[1;30m\]| \[\e[m\]\[\e[1;34m\]\w\[\e[m\] \[\e[1;29m\]\t\[\e[m\]]\[\e[1;33m\]$\[\e[m\]"
    thelaser · 2017-03-24 14:21:20 0

  • -2
    export PS1='[\[\e[36;1m\]\u@\[\e[32;1m\]\h \[\e[31;1m\]\w]# \[\e[0m\]'
    bakhru · 2011-04-16 00:58:51 2

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