There is potential for confusion if an octal or hexadecimal escape sequence is followed by other characters. For example, the character constant '\x1f' consists of a single character whereas the character constant '\x1g' consists of the two characters '\x1' and 'g'. The manner in which multi-character constants are represented as integers is implementation-defined.

The potential for confusion is reduced if every octal or hexadecimal escape sequence in a character constant or string literal is terminated.

Example

In this example, each of the strings pointed to by s1, s2 and s3 is equivalent to “Ag”.

const char *s1 = "\x41g";    /* Non-compliant                            */ 
const char *s2 = "\x41" "g"; /* Compliant - terminated by end of literal */ 
const char *s3 = "\x41\x67"; /* Compliant - terminated by another escape */

int c1 = '\141t';            /* Non-compliant                            */ 
int c2 = '\141\t';           /* Compliant - terminated by another escape */

MISRA.TOKEN.UNTERMINATED.ESCAPE.2012

MISRA C 2012 Rule 4.1: Octal and hexadecimal escape sequences shall be terminated

Amplification

Rationale

Example

See also