Split one file into multiple files based on pattern

The RS variable in awk is nice for this, allowing you to define the record separator. Thus, you just need to capture each record in its own temp file. The simplest version is:

cat temp |
  awk -v RS="3d3d" '{ print $0 > "temp" NR }' 

The sample text starts with the eye-catcher 3d3d, so temp1 will be an empty file. Further, the eye-catcher itself won't be at the start of the temp files, as was shown for the temp files in the question. Finally, if there are a lot of records, you could run into the system limit on open files. Some minor complications will bring it closer to what you want and make it safer:

cat temp |
  awk -v RS="3d3d" 'NR > 1 { print RS $0 > "temp" (NR-1); close("temp" (NR-1)) }' 

This might work:

# sed 's/3d3d/\n&/2g' temp | split -dl1 - temp
# ls
temp temp00  temp01  temp02
# cat temp00
3d3d01f87347545002f1d5b2be4ee4d700010100018000cc57e5820000000000000000000000000087d3f513000000000000000000000000000000000001001001010f000000000026 58783100b354c52658783100b4
# cat temp01
3d3d0000ad6413400103231665f301010b9130194899f2ffffffffffff02007c00dc015800a040402802f1d5b2b8ca5674504f4330310000000000046363070000000000000000000000000065450000b4fb6b400039
# cat temp02
3d3d1116cdcc57e58287d3f55285a1084b

EDIT:

If there are newlines in the source file you can remove them first by using tr -d '\n' <temp and then pipe the output through the above sed command. If however you wish to preserve them then:

 sed 's/3d3d/\n&/g;s/^\n\(3d3d\)/\1/' temp |csplit -zf temp - '/^3d3d/' {*}

Should do the trick

#!/usr/bin/perl

undef $/;
$_ = <>;
$n = 0;

for $match (split(/(?=3d3d)/)) {
      open(O, '>temp' . ++$n);
      print O $match;
      close(O);
}