This is sockets/is_seqnum.h (Listing 59-5, page 1220), an example from the book, The Linux Programming Interface.
The source code file is copyright 2022, Michael Kerrisk, and is licensed under the GNU General Public License, version 3.
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In the listing below, the names of Linux system calls and C library functions are hyperlinked to manual pages from the Linux man-pages project, and the names of functions implemented in the book are hyperlinked to the implementations of those functions.
/* is_seqnum.h Header file for is_seqnum_sv.c and is_seqnum_cl.c. */ #include <netinet/in.h> #include <sys/socket.h> #include <signal.h> #include "read_line.h" /* Declaration of readLine() */ #include "tlpi_hdr.h" #define PORT_NUM "50000" /* Port number for server */ #define INT_LEN 30 /* Size of string able to hold largest integer (including terminating '\n') */
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