linux - storing logs/error message on C programming -

when error occurs, c code store error before exiting program. advised store stderr file (e.g., /home/logs.txt) or advised use different method keep logs/error report (considering programming environment linux). e.g., code below, how apply method store logs/error message on /home/log.txt or /home/log

file *fp1; fp1 = fopen("/sys/class/gpio/export","w");  if(fp1 == null){     fprintf(stderr, "errno:%s - opening gpio136 failed - line 739\n ", strerror(errno));     close(fp1);     exit(1); } 

thank you.

if stderr used print out error message, so, can redirect output specific file.

$ program 2>~/logs.txt 

for better logging tool, can use:

• syslog standard function.

• log4c library.