linux - Pass last command status to $PS1 function -

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• bash prompt last exit code 4 answers

so have below code generating command line prompt:

function custom_prompt {     local black="\\[\\033[38;5;0m\\]";     local red="\\[\\033[38;5;1m\\]";     local green="\\[\\033[38;5;2m\\]";     local yellow="\\[\\033[38;5;3m\\]";     local blue="\\[\\033[38;5;4m\\]";     local magenta="\\[\\033[38;5;5m\\]";     local cyan="\\[\\033[38;5;6m\\]";     local lgray="\\[\\033[38;5;7m\\]";     local gray="\\[\\033[38;5;8m\\]";     local lred="\\[\\033[38;5;9m\\]";     local lgreen="\\[\\033[38;5;10m\\]";     local lyellow="\\[\\033[38;5;11m\\]";     local lblue="\\[\\033[38;5;12m\\]";     local lmagenta="\\[\\033[38;5;13m\\]";     local lcyan="\\[\\033[38;5;14m\\]";     local white="\\[$(tput sgr0)\\]";     local bold="\\[$(tput bold)\\]";      local n="\\n";      local user="`whoami`";     local host="`hostname`";     local path=$white"`pwd`";     local date=$magenta"`date`"$white;     local items="$(ls -a1 | wc -l | sed 's: ::g') items"     local folders="$(ls -ap1 | grep / | wc -l | sed 's: ::g') folders"     local files="$(ls -ap1 | grep -v / | wc -l | sed 's: ::g') files"     local size="$(/bin/ls -lah | /bin/grep -m 1 total | /bin/sed 's/total //')b"     local listing=$cyan"("$folders", "$files", "$size")"$white     local bash=$white"$"     if [[ $euid -eq 0 ]];         local user=$lred$user$white;         local bash=$white"#";     else         local user=$lgreen$user$white;     fi     if [[ $1 -eq 0 ]];         local check=$lgreen"✔"$white;     else         local check=$lred"✘"$white;     fi     local authority=$user$lgreen"@"$host$white;      echo $n$authority" "$listing" "$path$n$date" "$check" "$bash": "; } export ps1="`custom_prompt \$?`"; 

the problem in these lines:

# ... if [[ $1 -eq 0 ]];     local check=$lgreen"✔"$white; else     local check=$lred"✘"$white; fi # ... export ps1="`custom_prompt \$?`"; 

i trying check see if last command had error. however, can't seem figure out how pass information correctly if statement work.

my question: how pass value of $? custom_prompt?

you can try running function prompt_command, if uderstood trying (and sure not execute before value of $? otherwise value change):

function custom_prompt {      # $? first it's not modified other command     local exit_status=$?      local black="\\[\\033[38;5;0m\\]";     local red="\\[\\033[38;5;1m\\]";     local green="\\[\\033[38;5;2m\\]";     local yellow="\\[\\033[38;5;3m\\]";     local blue="\\[\\033[38;5;4m\\]";     local magenta="\\[\\033[38;5;5m\\]";     local cyan="\\[\\033[38;5;6m\\]";     local lgray="\\[\\033[38;5;7m\\]";     local gray="\\[\\033[38;5;8m\\]";     local lred="\\[\\033[38;5;9m\\]";     local lgreen="\\[\\033[38;5;10m\\]";     local lyellow="\\[\\033[38;5;11m\\]";     local lblue="\\[\\033[38;5;12m\\]";     local lmagenta="\\[\\033[38;5;13m\\]";     local lcyan="\\[\\033[38;5;14m\\]";     local white="\\[$(tput sgr0)\\]";     local bold="\\[$(tput bold)\\]";      local n="\\n";      local user="`whoami`";     local host="`hostname`";     local path=$white"`pwd`";     local date=$magenta"`date`"$white;     local items="$(ls -a1 | wc -l | sed 's: ::g') items"     local folders="$(ls -ap1 | grep / | wc -l | sed 's: ::g') folders"     local files="$(ls -ap1 | grep -v / | wc -l | sed 's: ::g') files"     local size="$(/bin/ls -lah | /bin/grep -m 1 total | /bin/sed 's/total //')b"     local listing=$cyan"("$folders", "$files", "$size")"$white     local bash=$white"$"     if [[ $euid -eq 0 ]];          local user=$lred$user$white;          local bash=$white"#";     else          local user=$lgreen$user$white;     fi     if [[ $exit_status -eq 0 ]];          local check=$lgreen"✔"$white;     else        local check=$lred"✘"$white;     fi     local authority=$user$lgreen"@"$host$white;      ps1=$n$authority" "$listing" "$path$n$date" "$check" "$bash": ";  }  prompt_command=custom_prompt