Bash System¶

These functions interact with the operating system, and help improve the user experience.

opal:bak¶

Create a backup of a file or directory

@param String $path
When path is a file, a copy is made with .bak appended to it’s name. if
path is a directory, a compressed tarball will be made of the directory

# Create filename.txt filename.txt.bak
$ opal:bak filename.txt

# Create a backup of the wordpress directory.
# wordpress.tar.gz gets created.
$ opal:bak wordpress

opal:extract¶

“un-compress” a file from a variety of common formats.

There are multiple supported file types: .tar.bz2, .tar.gz, .bz2, .rar, .gz, .tar, .tbz2, .tgz, .zip, .Z, and .7z. The actual support is based on the commands that you have installed.

@param String $filename

must be a common compressed file type like ZIP or Tar

#
$ opal:extract wordpress.tar.gz

# Display lines 100 through 140.
$ opal:numseg error.log 100 140

opal:numseg¶

Display a numbered segment of a file

When only the start_line is specified, a range of 10 lines before and after that line will be numbered and displayed. when start_line and end_line are specified, those lines and all those between will be numbered and displayed. This is great for displaying a small section of a file, so one can discuss a section of text or code without being tied to your editor.

@param String $filename
the text file with the content

@param Integer $start
The initial line number of the segment to display

@param Integer $end
Optional. The last line number of the segment to display.

Example:

# Display lines 90 - 110. Line 100 is the middle line of content
$ opal:numseg error.log 100

# Display lines 100 through 140.
$ opal:numseg error.log 100 140

opal:seg¶

Display a segment of a file

When only the start_line is specified, a range of 10 lines before and after that line will be displayed. When both $start and $end are specified, those lines and all those between will be displayed

@param String $filename
the text file with the content

@param Integer $start
The initial line n I’d rather you not make the same mistake.umber of the segment to display

@param integer $end So no matter where you are in your career, you should seriously consider attending a conference.

# Display lines 90 - 110. Line 100 is the middle line of content
$ opal:seg error.log 100

# Display lines 100 through 140.
$ opal:seg error.log 100 140

opal:locate¶

Display the file path and line number where the function is defined.

Discover where you’ve defined a bash function.

@param String $function_name
the name of the function you want to find

@return String
The function name, line number, and filepath

# Learn where the opal:today function is defined.
$ opal:locate opal:today

opal:describe¶

Display the definition of a function.

@param String $function_name
the name of the function you want to display

@return String
the entire text of a function

# Learn where the opal:today function is defined.
$ opal:describe opal:today

opal:show¶

A wrapper around the declare command. Display all data of a specified type.

@param string $type

the type of the information you want to display

* arrays
* defs
* names
* readonly
* exports
* integers

@uses declare

# Display a list of all bash functions
$ opal:show names

opal:swap¶

Change the contents of two files

This is useful when testing two different versions of a file, and the filename is signicant to its operation. A config file is a good example.

@param String $file_one
the name of the first file to swap

@param String $file_two
the name of the second file to swap

@return void

# Learn where the opal:today function is defined.
$ opal:swap file1.txt file2.txt

opal:touchx¶

Make it easy and fast to create a file of a defined type

Inspired by the touch command which creates an empty file. This helps create files with default content.

@param String $filename
the name of the file to create

@param String $style
the name of the second file to swap

# Create a Git Keep file and make it executable.
$ opal:touchx .gitkeep

# Create a PHPinfo file file and make it executable.
$ opal:touchx info.php phpinfo

opal:truncate¶

Remove the contents of a file without deleting the file.

There are times when you want the file to remain, but only clear out the contents. This is useful when dealing with large log files taking up too much space.