cc -g -Wall -lcrypt -o 01-crypt 01-crypt.c
01-crypt.c: In function ‘main‘:
01-crypt.c:35:5: warning: implicit declaration of function ‘strcpy‘ [-Wimplicit-function-declaration]
strcpy(passwd, crypt(key, slat));
^
01-crypt.c:35:5: warning: incompatible implicit declaration of built-in function ‘strcpy‘
01-crypt.c:35:5: note: include ‘<string.h>‘ or provide a declaration of ‘strcpy‘
01-crypt.c:35:20: warning: implicit declaration of function ‘crypt‘ [-Wimplicit-function-declaration]
strcpy(passwd, crypt(key, slat));
^
01-crypt.c:35:20: warning: passing argument 2 of ‘strcpy‘ makes pointer from integer without a cast [-Wint-conversion]
01-crypt.c:35:20: note: expected ‘const char *‘ but argument is of type ‘int‘
01-crypt.c:41:12: warning: format ‘%s‘ expects argument of type ‘char *‘, but argument 2 has type ‘int‘ [-Wformat=]
printf("After crypt(), 2nd passwd :%s\n", crypt(key, slat));
^
/tmp/ccCPHk2r.o: In function `main‘:
/home/fly/pub_work/04-linuxC/3stLinuxC/07-DataAlgorithms/01-crypt.c:35: undefined reference to `crypt‘
/home/fly/pub_work/04-linuxC/3stLinuxC/07-DataAlgorithms/01-crypt.c:41: undefined reference to `crypt‘
collect2: error: ld returned 1 exit status
Makefile:10: recipe for target ‘01-crypt‘ failed
make: *** [01-crypt] Error 1

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