Two independent shell lists connect through HISTFILE: session A appends with -a, and session B imports with -n.

Bash history is your searchable command log

A useful command history saves retyping, but it is not a complete record of everything executed. Bash normally enables history in interactive shells, and settings can exclude entries or limit retention. The searchable list in a running shell and the history file on disk are separate states. That distinction explains why a command may be visible in one terminal, absent in another, and lost when an unwritten session ends unexpectedly. ...

February 28, 2028 · 5 min · XB Field Notes
One ./*.txt pattern becomes three separate Bash arguments, including ./two words.txt intact.

Bash globbing expands before the command runs

A wildcard in a Bash command usually becomes a list of pathnames before the target program starts. That makes *.txt convenient, but it also makes the command depend on the current directory and shell options. The program receives arguments, without information saying which ones came from a wildcard. Decide whether you intend to pass matching files or a pattern for the program to interpret. ...

September 8, 2027 · 4 min · XB Field Notes