Opened 4 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?
