Problems in downloading large files via HTTP (WM5-WM6.1)
The Jargon Reader deployment engine is used to run all Jargon ForceField applications.
Jargon Reader provides low level HTTP methods to allow applications to download large binary files (such as ForceField's price matrix/bar code database built on the server and downloaded into place).
The Jargon Reader deployment engine utilizes HTTP methods for this purpose using the MS winInet library (same library that Pocket IE uses).
There are no issues when this is used in Pocket PC (WM4), or WM6.5 environments.
WM5 (and WM6.1) present a problem in that many times the large binary file being downloaded gets truncated midway (can be a minor to severe truncation), and that apps do not know this truncation occured, which causes subsequent support issues down the line.
When using Pocket IE to download the same files in the same memory situation as Jargon Reader, Pocket IE fails identically.
Examples:
Downloading to a ramdisk (can replicate at will) with MC70 (WM5) - 56MB Program memory total
1st attempt: Program memory at start 13.42 MB. atempting to download a 9.1 MB file. Pocket IE succeeds.
2nd attempt: Program memory reduced to 3.19 MB. Clearing Pocket IE cache or exiting IE has no effect on freeing up any program memory. Pocket IE fails with very low program memory error.
Downloading to root folder storage memory (can replicate at will) using MC70 (WM5) - 56 MB Program memory total:
1st attempt: Program memory at start 13.42 MB. atempting to download a 9.1 MB file. Pocket IE succeeds.
2nd attempt: Program memory reduced to 20.8 MB. Clearing Pocket IE cache or exiting IE has no effect on freeing up any program memory. Pocket IE succeeds.
3nd attempt: Program memory reduced to 11.41 MB. Clearing Pocket IE cache or exiting IE has no effect on freeing up any program memory. Pocket IE succeeds.
2nd attempt: Program memory reduced to 2.18 MB. Clearing Pocket IE cache or exiting IE has no effect on freeing up any program memory. Pocket IEfails with very low program memory error.
For both scenerios using the MC70 it appears to delete the file that is to be subsequently overlaid by the next download. During download the file is not visible in Win Explorer. When the file is downloaded successfully, then it appears in win explorder.
The only thing that frees up the program memory is to do a warm reset.
brief experimentation using an MC9090 (WM6.1) will also crash Pocket IE in a similar manner as above MC70 except that when the file downloaded, overlaying it's previous copy, Pocket IE renames the file appending ".pdl", then, when the dowload successeds, it renames the file and drops the .pdl extension.
Point of this comment is that apparently Pocket IE file download is implemented somewhat differently on differernt versions of WM so generalizations are difficult to draw.
MC5040 WM4 (Pocket PC) has no download issues, nor WM6.5