Solaris

$ make
gcc -Wall -O  -lcrypto -o sscep sscep.o init.o net.o sceputils.o pkcs7.o ias.o fileutils.o
Undefined                       first referenced
 symbol                             in file
bind                                net.o  (symbol belongs to implicit dependency /usr/lib/libsocket.so.1)
send                                net.o  (symbol belongs to implicit dependency /usr/lib/libsocket.so.1)
asn1_const_Finish                   ias.o
gethostbyname                       net.o  (symbol belongs to implicit dependency /usr/lib/libnsl.so.1)
socket                              net.o  (symbol belongs to implicit dependency /usr/lib/libsocket.so.1)
connect                             net.o  (symbol belongs to implicit dependency /usr/lib/libsocket.so.1)
ld: fatal: Symbol referencing errors. No output written to sscep
collect2: ld returned 1 exit status
*** Error code 1
make: Fatal error: Command failed for target `sscep'

$ uname -a
SunOS ffg0953zv1 5.10 Generic_139555-08 sun4v sparc SUNW,Sun-Blade-T6320

$ which make; which ld
/usr/ccs/bin/make
/usr/ccs/bin/ld

gcc -Wall -O  -lcrypto -o sscep sscep.o init.o net.o sceputils.o pkcs7.o ias.o fileutils.o \
  -lsocklet -lnsl