Reception excellent, but empty output.bits file

[Botox200]

I started the reception on Ubuntu 22.04 with a nooelec smarttee.

hrf1@hrf1:~/sniff/iridium$ iridium-extractor -D 4 rtl-sdr.conf | grep "A:OK" > output.bits

i get

gr-osmosdr 0.2.0.0 (0.2.0) gnuradio 3.10.1.1 built-in source types: file fcd rtl rtl_tcp hackrf rfspace soapy redpitaya Using device #0 Realtek RTL2838UHIDIR SN: 00000001 Found Elonics E4000 tuner Exact sample rate is: 2000000.052982 Hz (RF) Gain: 19.0 (Requested 19) IF Gain: 30.0 (Requested 30) Bandwidth: 0.0 (Requested 0) Warning: Setting antenna to RX 1701945876 | i: 0/s | i_avg: 0/s | q_max: 0 | i_ok: 0% | o: 0/s | ok: 0% | ok: 0/s | ok_avg: 0% | ok: 0 | ok_avg: 0/s | d: 0 Allocating 15 zero-copy buffers 1701945877 | i: 0/s | i_avg: 0/s | q_max: 0 | i_ok: 0% | o: 0/s | ok: 0% | ok: 0/s | ok_avg: 0% | ok: 0 | ok_avg: 0/s | d: 0 1701945878 | i: 1/s | i_avg: 0/s | q_max: 1 | i_ok: 100% | o: 2/s | ok: 100% | ok: 1/s | ok_avg: 100% | ok: 2 | ok_avg: 0/s | d: 0 1701945879 | i: 7/s | i_avg: 2/s | q_max: 2 | i_ok: 87% | o: 15/s | ok: 87% | ok: 6/s | ok_avg: 90% | ok: 9 | ok_avg: 2/s | d: 0 1701945880 | i: 5/s | i_avg: 3/s | q_max: 3 | i_ok: 33% | o: 11/s | ok: 33% | ok: 1/s | ok_avg: 68% | ok: 11 | ok_avg: 2/s | d: 0 1701945881 | i: 0/s | i_avg: 2/s | q_max: 1 | i_ok: 100% | o: 0/s | ok: 100% | ok: 0/s | ok_avg: 70% | ok: 12 | ok_avg: 2/s | d: 0

Although data is received and written, the output.bits file created is empty

hrf1@hrf1:~/sniff/iridium$ ls -l

results in

total 0 -rw-r--r-- 1 hrf1 hrf1 0 Dez 7 11:44 output.bits -rw-r--r-- 1 hrf1 hrf1 0 Dez 7 11:26 output.parsed

What might be the problem?
Thank you

[Botox200]

I removed the
grep "A:OK"

command, and then the file will be written correctly.