chaitanyav

/*
 * Author: NagaChaitanya Vellanki
 *
 *
 *
 * mtrace and muntrace example
 *
 * Running the program and sample output:
 *
 * gcc -Wall -pedantic -o mtrace_and_muntrace mtrace_and_muntrace.c

chaitanyav

/*
 * Author: NagaChaitanya Vellanki
 *
 *
 * calloc and realloc example
 *  gcc -Wall -pedantic -o calloc_and_realloc calloc_and_realloc.c
 * ------------------------------------------------------------
 * export MALLOC_TRACE=/tmp/t
 * ------------------------------------------------------------
 * ./calloc_and_realloc

chaitanyav

/*
 * Author: NagaChaitanya Vellanki
 *
 *
 * search for a key in an array,
 * if key is found return pointer to key
 * else return NULL
 */

#include <stdio.h>

chaitanyav

/*
 * Author: NagaChaitanya Vellanki
 *
 * ./read_passwd_file root 3
 *
 *  sample output
 *  -------------------------------
 *   Read /etc/passwd file
 *   Login name: root

chaitanyav

/*
 *
 * Author: NagaChaitanya Vellanki
 *
 *
 * Read entries in the passwd one at a time using getpwent
 */

#include <pwd.h>

chaitanyav

/*
 * Author: NagaChaitanya Vellanki
 *
 *
 * ./read_group_file sys 0
 *
 *  sample output
 *  ---------------------

chaitanyav

/*
 * Author: NagaChaitanya Vellanki
 *
 *
 * Read entries in the groups file one at a time
 */

#include <grp.h>
#include <stdio.h>

chaitanyav

/*
 * Author: NagaChaitanya Vellanki
 *
 * Refer to Listing 8-2 of LPI book
 *
 * Authenticate user against the /etc/shadow
 * gcc -Wall -pedantic -o check_user_password check_user_password.c -lcrypt
 *
 * sudo ./check_user_password

chaitanyav

/*
 * Author: NagaChaitanya Vellanki
 *
 *
 *
 * uptime command implementation
 */

#include <errno.h>

chaitanyav

/*
 *  Author: NagaChaitanya Vellanki
 *
 *see listing 10-2 of LPI book
 */

#include <stdio.h>
#include <stdlib.h>
#include <time.h>