set shell

Synopsis

/set shell [<program>]
/set -shell

Default: /bin/sh. With no program, set displays the current value. Unsetting selects direct execution for subsequent processes rather than restoring the default shell.

Description

Names the program normally spawned to execute commands launched by exec. This is generally a command shell, although it can be another program compatible with the arguments EPIC supplies. Required command-line switches belong in shell_flags.

The shell invocation consists of the configured program, the entire shell_flags string as one argument, and the command text as one argument. With the defaults, this corresponds to:

/bin/sh -c <command text>

The program value is used directly as an executable pathname with execl; EPIC does not search PATH for it or split it into a program and options. Set a usable pathname, and keep switches out of this value. The default is not selected from the SHELL environment variable.

Direct execution and effects

exec -direct bypasses this setting for that process. Unsetting shell also selects the direct path: EPIC splits the command into arguments, honors double-quoted words, and uses execvp, which can search PATH. Shell-specific pipelines, redirections, wildcard expansion, and variable expansion are not provided by that direct launch step.

Changing this setting does not launch a program or alter processes already running. EPIC does not validate the executable when assigning it. A launch failure is reported by the child as Error running program ..., followed by the operating system's error text.

Exec processes receive pipes for their standard streams and TERM=tty, not an interactive terminal. Choosing a shell does not make exec an interactive terminal session. Available shells and their command syntax depend on the local system; this setting sends no IRC request.

Example

Restore the standard shell and flags explicitly, then execute a command:

/set shell /bin/sh
/set shell_flags -c
/exec echo hello

To bypass the shell for one invocation, use /exec -direct echo hello instead.

Source references

• source/vars.c and include/config.h: string registration and /bin/sh default.
• source/exec.c: start_process selects shell or direct execution, sets up pipes and TERM, and reports launch failures; exec option parsing handles -direct.