Opened 2 years ago
#9940 new defect
sendcmd Error occurred in mmap()
Reported by: | Jozef Chutka | Owned by: | |
---|---|---|---|
Priority: | normal | Component: | undetermined |
Version: | unspecified | Keywords: | |
Cc: | Blocked By: | ||
Blocking: | Reproduced by developer: | no | |
Analyzed by developer: | no |
Description
Using the latest ffmpeg compiled with emscripten, I am not able to resolve [Parsed_sendcmd_6 @ 0x280af40] [FILE @ 0x17f3690] Error occurred in mmap(): No such device
error when using sendcmd=f=/mydir/myfile.txt
.
I have a readonly FS mounted as /mydir
but for some reason ffmpeg can not resolve /mydir/myfile.txt
which surely does exist.
Interestingly I can use movie=/mydir/myinput.mp4
to load input from the same FS.
I tried to understand what is the difference between reading a file from sendcmd
vs. movie
and it seems the first is using mmap()
(inside av_file_map()) while the other io_open()
(inside AVFormatContext, sorry not able to locate deeper) and reads it as an IO Stream... (?)
Reading file.c, I can see some other opening procedures based on HAVE_MMAP / HAVE_MAPVIEWOFFILE, but I am not sure how or if this can be available with emscripten build.
I wonder if this is something that can be resolved on my side or something ffmpeg team can take a look into?