add $8, $esp

# signtest.s - An example of using the sign flag
.section .data
value:
.int 21, 15, 34, 11, 6, 50, 32, 80, 10, 2
output:
.asciz "The value is: %d\n"
.section .text
.globl _start
_start:
movl $9, %edi
loop:
pushl value(, %edi, 4)
pushl $output
call printf
add $8, $esp
dec %edi
jns loop
movl $1, %eax
movl $0, %ebx
int $0x80

~/asm/jumps$ as -o signed.o signed.s 
signed.s: Assembler messages:
signed.s:12: Error: suffix or operands invalid for `push'
signed.s:13: Error: suffix or operands invalid for `push'
signed.s:15: Error: suffix or operands invalid for `add'
~/asm/jumps$ 

~/asm/jumps$ as --32 -o signed.o signed.s 
signed.s: Assembler messages:
signed.s:15: Error: suffix or operands invalid for `add'
~/asm/jumps$ 

isdigit(var_a_comprovar);

static char *convert_md5(char const *pwd)
{
	static char md5[34];
	char c[3];
    MD5_CTX context;
    int i;
    unsigned char digest[16];
    unsigned int len = strlen (pwd);
    
		MD5_Init(&context);
		MD5_Update (&context, pwd, len);
		MD5_Final(digest, &context);
		memset(md5, 0, sizeof(md5));
		
		for (i = 0; i < 16; i++) {
			snprintf(c, 3, "%02x", digest[i]);
			strncat(md5, c, sizeof(md5)-1); 
		}
    
	return md5;
}

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

int
main(int argc, char **argv)
{

        char test[20];

                fgets(test, sizeof(test)-1, stdin);
                test[strlen(test)-1] = '\0';
                printf("%s\n", test);
                return 0;
}