C Strings and my slow descent to madness

Re:C Strings and my slow descent to madness by tragomaskhalos on Thursday April 06, 2023 @06:52PM (#35475619)

K&R contains this beautiful koan-like string copy code:

    while (*t++ = *s++)
        ;

Honestly the elegance of this thing was one of the hooks that made me fall in love with C. But this was from a now-forgotten age of innocence, as there are so many "nopes" around this line-and-a-half that one would, rightly, be tarred and feathered for ever putting it in a program today.

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Re:C Strings and my slow descent to madness by kovac on Thursday April 06, 2023 @08:12PM (#35476364)

Could you explain why this line should be discouraged? I'm a beginner in C, so I really don't know. That's why I'm asking.

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Re:C Strings and my slow descent to madness by fatcow on Thursday April 06, 2023 @10:24PM (#35477266)

while (t++ = s++) ;

You're assigning a char to another, relying on the return value being 0 to detect end of string.

You're performing the copy while also increasing the pointers with ++ in the same expression.

You're using the cryptic ; empty statement to signify nop, thereby confusing newbies.

Etc

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Re:C Strings and my slow descent to madness by commandersaki on Friday April 07, 2023 @01:27AM (#35478353)

Equivalent of a strcpy() there's no bounds checking.

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Re:C Strings and my slow descent to madness by tragomaskhalos on Friday April 07, 2023 @04:39AM (#35479571)

Another reason, in addition to other replies and separate from safety concerns, is that strcpy, memcpy etc are nowadays usually implemented via more efficient compiler intrinsics rather than an explicit loop.

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