linux - Why PROMPT_COMMAND seems to be empty when i acces using system system call in c -


i have defined prompt_command in /etc/profile shown below,

 prompt_command = date

now when print prompt_command c code using system system call shown below not displaying anything,

system("echo pwd;echo whoami;echo \"p_cmd = $prompt_command\";eval $prompt_command");

output:

\root  root  p_cmd =

please clarify following doubt

why prompt_command showing empty?

you prompt_command has not been exported, try:

export prompt_command=date

-

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