bash's $PS0

I contributed a patch to add bash's PS0 variable; this was done in C and nroff. It allows things like (Note the "below cmd output" part):

$ echo start; sleep 5; echo finish below cmd output started 2015 Thu Nov 26 01:42:01 AM EST start finish above cmd output done 2015 Thu Nov 26 01:42:06 AM EST dstromberg@connserv:~ x86_64-unknown-linux-gnu 16606 $

...with the following in one's ~/.bashrc or similar:

export PS0="`tput smso`below cmd output started \D{%Y} \d \T \D{%p %Z}`tput rmso`\n"
export PS1="\[`tput smso`\]above cmd output done    \D{%Y} \d \T \D{%p %Z}\[`tput rmso`\]\n\[`tput smso`\]\u@\h:\w $MACHTYPE $PPID\[`tput rmso`\]\n\n\$ "

Note that I recommend source'ing your ~/.bashrc from your ~/.bash_profile .

The idea behind $PS0 is to make post mortems nicer, because you have not just the finish time of commands, but also the start time. I use it in tandem with hcm (and indirectly pypty) to get tty/pty logs with good time data.

Prior to $PS0, you could use trap DEBUG.

The $PS0 patch is included in bash 4.4; it was released 2016-09-15.

Here's a page about operating system support of $PS0.

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Timestamp: 2024-11-21 01:35:17 PST

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