char * strtrim(char* s ) to remove any space character(such as '\t' , ' ' ...) in a string

here is the function

char * strtrim(char* s )

it's designed to remove any space character(such as '\t' , ' ' ...) in a string

char* strtrim(char* s)
{

int len=0,i=0,j=0,k=0;
len = strlen(s);
if( len == 0 ) return NULL;

j = len -1;
while(s[j] == ' ' || s[i] == '\t' )
{
s[j--] = '\0';
if(j < 0 ) break;
}

while( s[i] == ' ' || s[i] == '\t' )  i++;
if( i == 0 ) return s;
while( s[k] != '\0') s[k++] = s[i++];

return s;

}