$ echo "toto" | openssl dgst -md5 -verify public_key -signature thesig.sig
Error opening key file public_key
26004:error:02001002:system library:fopen:No such file or directory:bss_file.c:352:fopen('public_key','r')
26004:error:20074002:BIO routines:FILE_CTRL:system lib:bss_file.c:354:
unable to load key file
$ echo $?
0

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