Differing Features
The following table is a sampling of features that are different among the three shells:
| Meaning/Action | bash | csh | tcsh |
|---|---|---|---|
| Default prompt. | $ | % | % |
| Force redirection. | >|
| >!
| >!
|
| Force append. | >>!
| >>!
| |
| Variable assignment. | var=val | set var=val
| set var=val
|
| Set environment variable. | export var=val
| setenv var val
| setenv var val
|
| Number of arguments. | $#
| $#argv
| $#argv
|
| Exit status. | $?
| $status
| $?
|
| Execute commands in file. | file | sourcefile
| source file
|
| End a loop statement. | done
| end
| end
|
| End case or switch. | esac
| endsw
| endsw
|
| Loop through variables. | for/do
| foreach
| foreach
|
| Sample if statement. | if [ $i -eq 5 ]
| if ($i==5)
| if ($i==5)
|
| End if statement. | fi
| endif
| endif
|
| Set resource limits. | ulimit
| limit
| limit
|
| Read from terminal. | read
| $<
| $<
|
| Make a variable read-only. | readonly
| set -r
| |
| File inquiry operator; tests for nonzero size. | -s
| ||
| Complete current word. | Tab | Tab | |
| Ignore interrupts. | trap 2
| onintr
| onintr
|
| Begin until loop. | until/do
| until
| until
|
| Begin while loop. | while/do
| while
| while |