c - Converting string to key_t -

c - Converting string to key_t -

how possible convert string key_t, in order utilize creating shared memory segment using shmget?

this because key mapping shared memory beingness transmitted on tcp/ip.

thanks in advance!

the key created phone call ftok(). latter uses file path , 8bit value so.

for same file path , same 8bit value ftok() (re-)creates same key.

so transfer file path , 8bit value (typically char) , allow receiver phone call ftok() on values received. create same key sender uses.

from ftok()'s documentation:

the ftok() function uses identity of file named given pathname (which must refer existing, accessible file) , to the lowest degree important 8 bits of proj_id (which must nonzero) generate key_t type scheme v ipc key, suitable utilize msgget(2), semget(2), or shmget(2).

the resulting value same pathnames name same file, when same value of proj_id used. value returned should different when (simultaneously existing) files or project ids differ.

c linux shared-memory sysv-ipc