02-07-2001
$? is the built-in shell variable that holds the exit code of the last command executed in the shell. I think it is used in many shells, but I am not sure which ones exactly. I've used it in KSH and SH (as I recall, but I don't work in Bourne shell, mostly KSH). I do recall $? used to hold the exit code of the last command in the Bourne shell from a 10 year ago past project. Maybe after coffee the neurons with fire from this memory bank
Hope this helps clarify.
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1..126
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127
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255
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LEARN ABOUT NETBSD
script
SCRIPT(1) BSD General Commands Manual SCRIPT(1)
NAME
script -- make typescript of terminal session
SYNOPSIS
script [-adfpqr] [-c command] [file]
DESCRIPTION
script makes a typescript of everything printed on your terminal. It is useful for students who need a hardcopy record of an interactive
session as proof of an assignment, as the typescript file can be printed out later with lpr(1).
If the argument file is given, script saves all dialogue in file. If no file name is given, the typescript is saved in the file typescript.
Option:
-a Append the output to file or typescript, retaining the prior contents.
-c command
Run the named command instead of the shell. Useful for capturing the output of a program that behaves differently when associated
with a tty.
-d When playing back a session with the -p flag, don't sleep between records when playing back a timestamped session.
-f Flush output after each write. This is useful for watching the script output in real time.
-p Play back a session recorded with the -r flag in real time.
-q Be quiet, and don't output started and ended lines.
-r Record a session with input, output, and timestamping.
The script ends when the forked shell exits (a control-D to exit the Bourne shell (sh(1)), and exit, logout or control-d (if ignoreeof is not
set) for the C-shell, csh(1)).
Certain interactive commands, such as vi(1), create garbage in the typescript file. script works best with commands that do not manipulate
the screen, the results are meant to emulate a hardcopy terminal.
ENVIRONMENT
The following environment variable is used by script:
SHELL If the variable SHELL exists, the shell forked by script will be that shell. If SHELL is not set, the Bourne shell is assumed. (Most
shells set this variable automatically).
SEE ALSO
csh(1) (for the history mechanism).
HISTORY
The script command appeared in 3.0BSD.
BUGS
script places everything in the log file, including linefeeds and backspaces. This is not what the naive user expects.
BSD
October 17, 2009 BSD