Linux signal masks - what do they mean though? -

how can store 32 signals inside 16 bit mask?

sigpnd: 0000000000000000 shdpnd: 0000000000004000 sigblk: 0000010000017003 sigign: 0000000000381000 

how interpret sigign example? read proc documentation don't how interpret actual bits mean.

not sure got "32 signals inside 16 bit mask" information wrong far know.

assuming each line hex each line 8 bytes or 64 bits. lower 4 bytes (32 bits) standard signals. upper 32 bits posix realtime signals. (it's little more convoluted - see man (7) signal , sigrtmax , sigrtmin low down.)

so in sigign mask asked off couple of things in lower 3 bytes: 38 10 00. in lowest order byte, 00, no signals ignored. in next byte, hex 10 converts 00010000 in binary. 5th bit in byte on. likewise hex 38 converts binary 00111000. putting 3 bytes string of binary get:

001110000001000000000000 

so counting right can see bits 13 20 21 22 on , therefore ignored. if go man (7) signal can see table signal values. values broken down architecture so, assuming on ix86 machine, signal values represent sigpipe, sigtstp, sigttin , sigttou signals being ignored.