c musings

Some of the corner case are discussed in below links

fgets and char *s

1.fgets and char *s
why we should use

wrong way,

char *s;
fgets(s, 6, stdint);

right way

char *s;
s = malloc(sizeof(s)*5);
fgets(s, 6, stdint);

or

char s[10];
fgets(s, 6, stdint);


2. Why casting malloc is not a good idea

Malloc and casting

 Also using malloc like this

char  *s = malloc ( sizeof ( char ) * 5 );

is not good. Instead use it this way,

char *s = malloc ( sizeof ( *s ) * 5 );

for portability. if the type of s changes from  char to, say, float.

  malloc( sizeof (*s) * length );
 
will work regardless of the type.

Reasons for not casting is,

1.It is unnecessary, as void * is automatically and safely promoted to any other pointer type in this case.

2.It adds clutter to the code, casts are not very easy to read (especially if the pointer type is long).

3.It makes you repeat yourself, which is generally bad.