An issue in strcat manpage

[Eric Sanchis <eric.sanchis@xxxxxxxxxxxx>]

Dear Maintener,

The example illustrating the strcat function man page produces a
buffer owerflow (off-by-one
error). A typical trap of strcat.

The program below shows the problem:

#include <string.h>
#include <stdio.h>

       int
       main(int argc, char *argv[])
       {
       #define LIM 4
           char p[LIM];
       int j ;

           p[0] = '\0';

           for (j = 0; j < LIM; j++)
               strcat(p, "a");
       printf("(j=%d)  p='%s' -- psize : %d  -- plen=%u\n", j,p,LIM,
(unsigned int) strlen(p)) ;

           return 0 ;
       }

Execution:

$ prog
(j=4)  p='aaaa' -- psize : 4 -- plen=4
$

p should be 'aaa'.

Do you intend to fix this issue ?

Yours truly,

Eric Sanchis
Associate Professor in Computer Science
University of Toulouse Capitole (IUT Rodez)
France