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Exactly. We can't kill strcpy/strcat, for backward compatibility reasons. But the standard ought to have a spec that is actually useful and not ridiculously sub

Exactly. We can't kill strcpy/strcat, for backward compatibility reasons. But the standard ought to have a spec that is actually useful and not ridiculously sub-optimal. strlcpy() doesn't fit the bill either.

nkurz 11y ago
I'm late to this discussion, but did you possibly miss stpcpy() and its variants? Or is something about them that doesn't meet your needs? STPCPY(3) Linux Programmer's Manual NAME stpcpy - copy a string returning a pointer to its end SYNOPSIS #include <string.h> char *stpcpy(char *dest, const char *src); Feature Test Macro Requirements for glibc (see feature_test_macros(7)): stpcpy(): Since glibc 2.10: _XOPEN_SOURCE >= 700 || _POSIX_C_SOURCE >= 200809L Before glibc 2.10: _GNU_SOURCE DESCRIPTION The stpcpy() function copies the string pointed to by src (including the terminating null byte ('\0')) to the array pointed to by dest. The strings may not overlap, and the destination string dest must be large enough to receive the copy. RETURN VALUE stpcpy() returns a pointer to the end of the string dest (that is, the address of the terminating null byte) rather than the beginning. CONFORMING TO This function was added to POSIX.1-2008. Before that, it was not part of the C or POSIX.1 standards, nor customary on UNIX systems, but was not a GNU invention either. Perhaps it came from MS-DOS. It is also present on the BSDs. BUGS This function may overrun the buffer dest. EXAMPLE For example, this program uses stpcpy() to concatenate foo and bar to produce foobar, which it then prints. #define _GNU_SOURCE #include <string.h> #include <stdio.h> int main(void) { char buffer[20]; char *to = buffer; to = stpcpy(to, "foo"); to = stpcpy(to, "bar"); printf("%s\n", buffer); } SEE ALSO memccpy(3), stpncpy(3), wcpcpy(3)
- hyc_symas 11y ago
  Added to POSIX is good, but not sufficient. E.g., there is no reason for Windows to implement a function merely because it's in the POSIX spec. It needs to be in the C spec to actually be viable. stpncpy is equivalent to strncpy - it NUL-pads dest if the src is shorter than N. Frankly I have never found a use for this behavior. The desired behavior is to simply copy src without additional padding. That is what my proposed strecopy() does, and that's what would be required of a replacement for strlcpy().

nkurz 11y ago

I'm late to this discussion, but did you possibly miss stpcpy() and its variants? Or is something about them that doesn't meet your needs? STPCPY(3) Linux Programmer's Manual NAME stpcpy - copy a string returning a pointer to its end SYNOPSIS #include <string.h> char *stpcpy(char *dest, const char *src); Feature Test Macro Requirements for glibc (see feature_test_macros(7)): stpcpy(): Since glibc 2.10: _XOPEN_SOURCE >= 700 || _POSIX_C_SOURCE >= 200809L Before glibc 2.10: _GNU_SOURCE DESCRIPTION The stpcpy() function copies the string pointed to by src (including the terminating null byte ('\0')) to the array pointed to by dest. The strings may not overlap, and the destination string dest must be large enough to receive the copy. RETURN VALUE stpcpy() returns a pointer to the end of the string dest (that is, the address of the terminating null byte) rather than the beginning. CONFORMING TO This function was added to POSIX.1-2008. Before that, it was not part of the C or POSIX.1 standards, nor customary on UNIX systems, but was not a GNU invention either. Perhaps it came from MS-DOS. It is also present on the BSDs. BUGS This function may overrun the buffer dest. EXAMPLE For example, this program uses stpcpy() to concatenate foo and bar to produce foobar, which it then prints. #define _GNU_SOURCE #include <string.h> #include <stdio.h> int main(void) { char buffer[20]; char *to = buffer; to = stpcpy(to, "foo"); to = stpcpy(to, "bar"); printf("%s\n", buffer); } SEE ALSO memccpy(3), stpncpy(3), wcpcpy(3)

hyc_symas 11y ago
Added to POSIX is good, but not sufficient. E.g., there is no reason for Windows to implement a function merely because it's in the POSIX spec. It needs to be in the C spec to actually be viable. stpncpy is equivalent to strncpy - it NUL-pads dest if the src is shorter than N. Frankly I have never found a use for this behavior. The desired behavior is to simply copy src without additional padding. That is what my proposed strecopy() does, and that's what would be required of a replacement for strlcpy().