GNU readline History feature

Question

I'm using this code for the history features in my shell: http://cc.byexamples.com/20080613/gnu-readline-how-to-keep-a-history-list-of-entered-command-lines/ but when I compile this using gcc, I got this error

$ gcc filename.c
/tmp/ccay2CgM.o: In function `main':
rl.c:(.text+0x9): undefined reference to `rl_abort'
rl.c:(.text+0x13): undefined reference to `rl_bind_key'
rl.c:(.text+0x1d): undefined reference to `readline'
rl.c:(.text+0x61): undefined reference to `add_history'
collect2: ld returned 1 exit status
$

Answer 1

The example compile line is

g++ -o simple_rl{,.cpp} -lreadline

Did you forget to add the -lreadline?