bash:built-in_variables
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| bash:built-in_variables [2017/04/03 15:34] – created peter | bash:built-in_variables [2021/01/26 11:42] (current) – peter | ||
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| When doing scripting in the shell there are a few built-in variables that we can used: | When doing scripting in the shell there are a few built-in variables that we can used: | ||
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| $$ = The PID number of the process executing the shell. | $$ = The PID number of the process executing the shell. | ||
| - | $? = Exit status variable. | + | $? = Exit status variable. Nearly all Linux programs return a 0 error status for true and anything else is false. |
| $0 = The name of the command you used to call a program. | $0 = The name of the command you used to call a program. | ||
| $1 = The first argument on the command line. | $1 = The first argument on the command line. | ||
bash/built-in_variables.1491233687.txt.gz · Last modified: 2020/07/15 09:30 (external edit)