36 lines
1.2 KiB
Markdown
36 lines
1.2 KiB
Markdown
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### Unix commands: a very brief summary
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| Command | Action |
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|:--------|:--------------------------------------------------------|
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| `ls` | view directory contents (`ls -l` for a long view) |
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| `rm` | remove files (`rm -r` to remove entire directory trees) |
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| `rmdir` | remove an empty directory |
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| `cp` | copy a file (`cp -a` to copy directory trees) |
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| `mv` | move a file or directory |
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| `cat` | output a file to screen |
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| `less` | view a file page-by-page, with scrollback |
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Command help texts can be accessed with the `--help` switch. Directories are
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separated by `/`, not `\`. The root of the filesystem is `/`. Drive letter
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`C:` is expressed as `/c/`.
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### Environment variables in Unix
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Environmental variables may be viewed with the `env` command. Individual
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variables may be viewed like this:
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```text
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$ echo $PATH
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```
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and set like this:
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```text
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$ PATH=$PATH:/home/<username>/bin
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```
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Sometimes variables must be exported to be visible to called programs:
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```text
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$ export PATH
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```
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