prog.c: In function ‘main’:
prog.c:8:2: warning: implicit declaration of function ‘gets’ [-Wimplicit-function-declaration]
gets(a);
^~~~
prog.c:10:38: warning: format ‘%d’ expects argument of type ‘int’, but argument 2 has type ‘size_t {aka long unsigned int}’ [-Wformat=]
printf("\n the length of string is %d",strlen(a));
^
prog.c:11:36: warning: implicit declaration of function ‘strupr’ [-Wimplicit-function-declaration]
printf("\n in upper string is %s",strupr(a));
^~~~~~
prog.c:11:33: warning: format ‘%s’ expects argument of type ‘char *’, but argument 2 has type ‘int’ [-Wformat=]
printf("\n in upper string is %s",strupr(a));
^
prog.c:12:32: warning: implicit declaration of function ‘strlwr’ [-Wimplicit-function-declaration]
printf("\n in lower case %s",strlwr(a));
^~~~~~
prog.c:12:29: warning: format ‘%s’ expects argument of type ‘char *’, but argument 2 has type ‘int’ [-Wformat=]
printf("\n in lower case %s",strlwr(a));
^
prog.c:15:2: warning: implicit declaration of function ‘strrev’ [-Wimplicit-function-declaration]
strrev(b);
^~~~~~
prog.c:18:2: warning: implicit declaration of function ‘getch’ [-Wimplicit-function-declaration]
getch();
^~~~~
/home/UsawA9/cciX00uh.o: In function `main':
prog.c:(.text.startup+0x20): warning: the `gets' function is dangerous and should not be used.
prog.c:(.text.startup+0x88): undefined reference to `strupr'
prog.c:(.text.startup+0xa2): undefined reference to `strlwr'
prog.c:(.text.startup+0xd8): undefined reference to `strrev'
prog.c:(.text.startup+0x10b): undefined reference to `getch'
collect2: error: ld returned 1 exit status