How to extract comment from ppm file?

I have ppm file X.ppm with comment : xxd X.ppm|head -10 0000000: 5036 0a23 206d 6967 6874 796d 616e 6465 P6.# mightymande 0000010: 6c20 2d32 2e38 3034 3132 3232 3037 3833 l -2.80412220783 0000020: 3834 3132 3833 3535 3139 3235 652d 3032 841283551925e-02 0000030: 202b 2036 2e39 3438 3932 3238 3438 3134 + 6.94892284814 0000040: 3730 3430 3430 3831 3238 3631 652d 3031 704040812861e-01 0000050: 2069 2040 2034 2e34 3430 3839 3230 3938 i @ 4.440892098 0000060: 3530 3036 3237 3165 2d31 360a 3132 3830 5006271e-16.1280 0000070: 2037 3230 0a32 3535 0aff ffff ffff ffff 720.255........ 0000080: ffff ffff ffff ffff ffff ffff ffff fefe ................ 0000090: fefc fcfc f8f8 f8e8 e8e8 4141 4140 4040 ..........AAA@@@ It is created with c code : void record_write(FILE *out, unsigned char *buffer, int width, int height, mpfr_t centerx, mpfr_t centery, mpfr_t radius) { fprintf(out, "P6\n"); mpfr_fprintf(out, "# mightymandel %Re + %Re i @ %Re\n", centerx, centery, radius); fprintf(out, "%d %d\n255\n", width, height); fflush(out); for (int y = height - 1; y >= 0; --y) { fwrite(buffer + y * width * 3, width * 3, 1, out); } fflush(out); } I can convert it to png : xxd X.png|head -10 0000000: 8950 4e47 0d0a 1a0a 0000 000d 4948 4452 .PNG........IHDR 0000010: 0000 0500 0000 02d0 0802 0000 0137 187a .............7.z 0000020: 9700 0000 5f74 4558 7454 6974 6c65 002d ...._tEXtTitle.- 0000030: 322e 3830 3431 3232 3230 3738 3338 3431 2.80412220783841 0000040: 3238 3335 3531 3932 3565 2d30 3220 2b20 283551925e-02 + 0000050: 362e 3934 3839 3232 3834 3831 3437 3034 6.94892284814704 0000060: 3034 3038 3132 3836 3165 2d30 3120 6920 040812861e-01 i 0000070: 4020 342e 3434 3038 3932 3039 3835 3030 @ 4.440892098500 0000080: 3632 3731 652d 3136 aba5 7721 0000 0015 6271e-16..w!.... 0000090: 7445 5874 536f 6674 7761 7265 006d 6967 tEXtSoftware.mig It also contain comment, but : - It is not exif ( and ppm is not supported by eviv2 library ). - Gimp also do not show comment from ppm or png file ( why ?) - identify -verbose X.ppm shows comment What program should I use to extract comment from ppm files ?