Fs.lua

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Filesystem Specific functions


is_dir

INPUT:
This library function required the following inputs/parameters.

  • Path to directory
    • Example: /var/log/snort

OUTPUT:
This library function deliverers the following output/parameters.

  • nil or "directory"
    • If inputstring is a existing directory, the output is "directory" (not nil)

CODING EXAMPLE:

-- Include/Call for this library
require("fs")
-- Check if url is a folder
liboutput = fs.is_dir("/var/log/snort")

If directory exist 'liboutput' would contain string:

directory

In directory is missing 'liboutput' would contain nil (nothing).

is_file

INPUT:
This library function required the following inputs/parameters.

  • Path to file
    • Example: /var/log/messages

OUTPUT:
This library function deliverers the following output/parameters.

  • nil or "file"
    • If inputstring is a existing file, the output is "file" (not nil)

CODING EXAMPLE:

-- Include/Call for this library
require("fs")
-- Check if url is a file
liboutput = fs.is_file("/var/log/messages")

If file exist 'liboutput' would contain string:

file

In file is missing 'liboutput' would contain nil (nothing).


is_link

INPUT:
This library function required the following inputs/parameters.

  • Path to link
    • Example: /etc/rcL.d/S50sshd

OUTPUT:
This library function deliverers the following output/parameters.

  • nil or "file"
    • If inputstring is a existing file, the output is "file" (not nil)

CODING EXAMPLE:

-- Include/Call for this library
require("fs")
-- Check if url is a file
liboutput = fs.is_link("/etc/rcL.d/S50sshd")

If file exist 'liboutput' would contain string:

file

In file is missing 'liboutput' would contain nil (nothing).

read_file / read_file_as_array

INPUT:
This library function required the following inputs/parameters.

  • Path to file
    • Example: /var/log/messages

OUTPUT:
This library function deliverers the following output/parameters.

  • Filecontent
    • The filecontent is presented as a string (output comes as a table if 'read_file_as_array' is used)

CODING EXAMPLE:

-- Include/Call for this library
require("fs")
-- Get filecontent
liboutput = fs.read_file("/var/log/messages")

'liboutput' could contain something like:

Nov  6 13:17:01 inspiron /USR/SBIN/CRON[21751]: (root) CMD (   cd / && run-parts --report /etc/cron.hourly)
Nov  6 13:43:31 inspiron -- MARK --

CODING EXAMPLE (read_file_as_array):
If 'read_file_as_array' is used, you could do something like this see the output:

for a,b in ipairs(liboutput) do print(a,b) end

The output would look something like:

1 Nov  6 13:17:01 inspiron /USR/SBIN/CRON[21751]: (root) CMD (   cd / && run-parts --report /etc/cron.hourly)
2 Nov  6 13:43:31 inspiron -- MARK --

write_file

INPUT:
This library function required the following inputs/parameters.

  • Path to file
    • Example: /root/mynotes
  • String
    • Content that should be written to file

OUTPUT:
This library function deliverers the following output/parameters.

  • Output is written to file
    • The content of the inputstring is written to the file.
    • Data is not appended to file

CODING EXAMPLE:

-- Include/Call for this library
require("fs")
-- Write to file
fs.write_file("/var/log/messages", "Hello World!")

find

Lets you search for dir entries matching filespec.
Could be compared to 'find / -type d | grep tmp' (not sure)
INPUT:
This library function required the following inputs/parameters.

  • SearchString
    • This string is what we are searching for in the dirnames.
  • Path
    • This path is where we start searching
    • Search is recursive (not sure)

OUTPUT:
This library function deliverers the following output/parameters.

  • SearchResult
    • The SearchResult as a table (array)

CODING EXAMPLE:

-- Include/Call for this library
require("fs")
-- Search for dir
liboutput = fs.find("tmp", "/") 

You could do something like this see the output:

for a,b in ipairs(liboutput) do print(a,b) end

The output would look something like:

1 /usr/tmp
2 /usr/tmp/apk_add