| Variable | Meaning
| $#
| Number of arguments given to current process.
| $@
| Command-line arguments to current process. Inside double
quotes, expands
to individual arguments.
| $*
| Command-line arguments to current process. Inside double
quotes, expands
to a single argument.
| $-
| (hyphen) Options given to shell on invocation.
| $?
| Exit status of previous command.
| $$
| Process ID of shell process.
| $0
| (zero) The name of the shell program.
| $!
| Process ID of last background command. Use this to save
process ID numbers
for later use with the wait command.
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special3.htm,
Sun Dec 14 23:14:45 CST 2025
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