Linux command
test 命令
文件
涉及管道、覆盖或删除，执行前请先确认路径和参数。
常用示例
Check if a file exists
test -e [path/to/file] && echo "exists"
Check if file is a directory
test -d [path/to/dir] && echo "is directory"
Check if file is readable
test -r [path/to/file] && echo "readable"
Compare strings for equality
test "[string1]" = "[string2]"
Check if string is non-empty
test -n "[string]"
Compare integers
test [5] -gt [3] && echo "greater"
Combine conditions with AND
test -f [file] -a -r [file]
Combine conditions with OR
test -f [file1] -o -f [file2]
说明
test evaluates conditional expressions, returning exit status 0 (true) or 1 (false). It is commonly used in shell scripts for decision-making in if statements and loops. The command can also be invoked as with a closing required as the last argument. This bracket syntax is more readable in conditionals: if -f file ; then. Modern shells also provide [[ which offers additional features like pattern matching and safer string handling, but is not POSIX-compliant.
FAQ
What is the test command used for?
test evaluates conditional expressions, returning exit status 0 (true) or 1 (false). It is commonly used in shell scripts for decision-making in if statements and loops. The command can also be invoked as with a closing required as the last argument. This bracket syntax is more readable in conditionals: if -f file ; then. Modern shells also provide [[ which offers additional features like pattern matching and safer string handling, but is not POSIX-compliant.
How do I run a basic test example?
Run `test -e [path/to/file] && echo "exists"` in a terminal, then adjust file names, paths, flags, or remote targets for your system.
Where can I find more test examples?
This page includes 8 examples for test, plus related commands for nearby Linux tasks.