Issue 0017.32: Are strcmp/strncmp defined when char is signed?

This issue has been automatically converted from the original issue lists and some formatting may not have been preserved.

Authors: Derek M. Jones, WG14
Date: 1992-12-10
Reference document: X3J11/90-056
Submitted against: C90
Status: Closed
Converted from: dr.htm, dr_017.html

char parameters to strcmp and strncmp

Refer to subclause 7.11.4, page 164. If char is signed then char * cannot be interpreted as pointing to unsigned char. The required cast may give undefined results. This applies to strcmp and strncmp.

Comment from WG14 on 1997-09-23:

Response

strcmp can compare two char strings, even though the representation of char may be signed, because subclause 7.11.4, page 164, line 7 says that the interpretation of bytes is done as if each byte were accessed as an unsigned char. We believe the standard is clear.