Hapter; File Systems; File Compression; Environment/Configuration Variables - VeriFone MX800 series Programmer's Manual

File Systems

File
Compression
Environment/
Configuration
Variables

File Format Details

x
The M 800 series terminal file system uses the Journaling Flash File System or
JFFS2. JFFS2 is used to store application code and data as well as shared
libraries. JFFS2 supports wear leveling and power fail protection.
x
The M 800 series of terminals will support GNU ZIP (.gz or .tgz or tar.gz)
compressed files. The system will support both creation and expansion of GNU
ZIP files. Downloaded files may be compressed. The TAR format is used to
combine multiple files into a single file. The resulting file may then be compressed.
This process produces a tar.gz file. Winzip can open a tar.gz file but it cannot
create one. There are a number of applications available to create tar.gz files on a
Windows platform.
Linux has long had the concept of environment variables (also called
configuration variables). Unfortunately, environment variables are not permanent
and Linux normally requires a shell script that sets the environment variables prior
x
to their use. The M 800 series of terminals will augment this process by having
files in battery backed SRAM to store configuration variables.
getenv() and putenv() are native functions to Linux. Using putenv() will set/
change/delete an environment variable but the value will not persist if a power
x
failure occurs. The M 800 series of terminals supports enhanced APIs
getEnvFile() and putEnvFile() to get or set environment variables in the
battery backed SRAM file system.
x
The M 800 series of terminals uses a standard file format to store configuration
variables. The file stores ASCII information in .ini format.
For example:
[perm]
i4683=R232
o4683=01234567
[reg]
store=sportworld
appid=1234
INI files consist of section headers (defined within [ ]) followed by keys (or
labels) and their associated values. For example, appid is a key with value 1234
and it resides under section reg.
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HAPTER

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M 800 S P
ERIES ROGRAMMERS
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