cc -O2 -pipe  -pthread  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations fmtmsg/MM_NOMSG.c -o fmtmsg/MM_NOMSG -D_POSIX_C_SOURCE=202405L  -lm -lpthread 
fmtmsg/MM_NOMSG.c:7:10: fatal error: 'fmtmsg.h' file not found
#include <fmtmsg.h>
         ^~~~~~~~~~
1 error generated.