c - Data type of command line args -

i'm struggling convert executable program function can call within main routine. written, executable looks this:

int main(int argc, char* argv[]){     //do stuff     if(setxattr(argv[4], tmpstr, argv[3], strlen(argv[3]), 0)){         perror("setxattr error");         exit(exit_failure);     }     //do more stuff } 

i can call follows , works successfully:

./set_attributes -s encrypted 1 ~/text.txt

but want move function embedded in program. part failing strlen(argv[3]). new function looks this:

int set_encr_attr(char* fpath, int value) {      char* userstr = null;      /* check value set either 0 or 1 */     if (!( (value == 0) || (value == 1) )) {         return -1;     }      //do stuff (including malloc(userstr)     strcpy(userstr, xattr_user_prefix);      /* set attribute */     if(setxattr(fpath, userstr, value, 1, 0)){         perror("setxattr error");         exit(exit_failure);     }      return exit_success; } 

as can see, i've replaced fourth argument number 1, since i've checked value being passed in either 0 or 1, must have strlen of 1. i've tried few other things, error:

xattr_new.c: in function ‘set_encr_attr’:

xattr_new.c:52:2: warning: passing argument 3 of ‘setxattr’ makes pointer integer without cast [enabled default]

/usr/include/i386-linux-gnu/sys/xattr.h:40:12: note: expected ‘const void *’ argument of type ‘int’

when play this, can see strlen(argv[3]) == 1, don't understand why can't replace integer 1. typing issue, i've tried casting (which think bad idea), can't make work.

can help? thanks!

1 integer, "1" string, character array of length 2, containing ascii character '1' (value 49) followed null byte (terminator). function doesn't want integer, wants char pointer. strlen("1") = 1 because string delimited null byte.