BEAUTY AND PLAY
A UNIX Command stat -f / $stat -f / File: “/” ID: bc427fdafb7b0541 Namelen: 255 Type: ext2/ext3 Block size: 4096 Fundamental block size: 4096 Blocks: Total: 18864769 Free: 16209639 Available: 15251363 Inodes: Total: 4792320 Free: 4684854 $ UNIX Explanation Display file or file system status. Related Source Code Exposition static bool do_statfs (char const *filename, …
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A UNIX Command . vmstat -m Cache Num Total Size Pages fat_inode_cache 23 23 688 23 fat_cache 102 102 40 102 isofs_inode_cache 0 0 656 12 udf_inode_cache 23 23 712 23 fuse_request 0 0 632 25 fuse_inode 0 0 768 21 dm_crypt_io 0 0 152 26 kcopyd_job 0 0 368 22 dm_uevent 0 0 2608 …
Continue reading “vmstat – Report virtual memory statistics”
vmstat reports information about processes, memory, paging, block IO, traps, disks and cpu activity. Slab Allocation Linux Slab Allocator.
commandline session $getopt hello — $getopt hello how are you ? — how are you 1 c h $getopt hello hello are you ? — hello are you 1 c h $getopt hello hello are yours ? — hello are yours 1 c h $getopt hello hello are yours what ? — hello are yours …
getopt is used to break up (parse) options in command lines for easy parsing by shell procedures, and to check for legal options.
Print the first 10 lines of each FILE to standard output. Part of debian coreutils.
commandline session head is a program on Unix and Unix-like operating systems used to display the beginning of a text file or piped data. $sudo head /var/log/syslog Jan 5 20:10:05 debian syslogd 1.5.0#6.1: restart. Jan 5 20:10:05 debian anacron[1056]: Job `cron.daily’ terminated Jan 5 20:10:05 debian anacron[1056]: Normal exit (1 job run) Jan 5 20:12:14 …
The hexdump utility is a filter which displays the specified files, or standard input if no files are specified, in a user-specified format. $cat version.c #include #include int main(int argc, char **argv) { printf(“MySQL client version: %sn”, mysql_get_client_info()); } Commandline Session $hexdump version.c 0000000 6923 636e 756c 10064 3c20 796d 675f 6f6c 0000010 6162 2e6c …
Continue reading “hexdump, hd — ASCII, decimal, hexadecimal, octal dump”
20.4 `groups’: Print group names a user is in ============================================= `groups’ prints the names of the primary and any supplementary groups for each given USERNAME, or the current process if no names are given. If more than one name is given, the name of each user is printed before the list of that user’s groups …
A UNIX Command $true $echo $? 0 $false $echo $? 1 $ UNIX Explanation true – do nothing, successfully exit with a status code indicating success. false – do nothing, unsuccessfully exit with a status code indicating failure. Related Source Code Exposition int main (int argc, char **argv) { if (argc == 2) { initialize_main …
