Visit Our UNIX and Linux User Community

Linux and UNIX Man Pages

Test Your Knowledge in Computers #17
Difficulty: Easy
Microsoft first developed the Java programming language.
True or False?
Linux & Unix Commands - Search Man Pages

vm_map_lock(9) [freebsd man page]

VM_MAP_LOCK(9)						   BSD Kernel Developer's Manual					    VM_MAP_LOCK(9)

NAME
vm_map_lock, vm_map_unlock, vm_map_lock_read, vm_map_unlock_read, vm_map_trylock, vm_map_trylock_read, vm_map_lock_upgrade, vm_map_lock_downgrade -- vm_map locking macros SYNOPSIS
#include <sys/param.h> #include <vm/vm.h> #include <vm/vm_map.h> void vm_map_lock(vm_map_t map); void vm_map_unlock(vm_map_t map); void vm_map_lock_read(vm_map_t map); void vm_map_unlock_read(vm_map_t map); int vm_map_trylock(vm_map_t map); int vm_map_trylock_read(vm_map_t map); int vm_map_lock_upgrade(vm_map_t map); int vm_map_lock_downgrade(vm_map_t map); DESCRIPTION
The vm_map_lock() macro obtains an exclusive lock on map. The vm_map_unlock() macro releases an exclusive lock on map. The vm_map_lock_read() macro obtains a read-lock on map. The vm_map_unlock_read() macro releases a read-lock on map. The vm_map_trylock() macro attempts to obtain an exclusive lock on map. It returns FALSE if the lock cannot be immediately acquired; other- wise return TRUE with the lock acquired. The vm_map_trylock_read() macro attempts to obtain a read-lock on map. It returns FALSE if the lock cannot be immediately acquired; other- wise return TRUE with the lock acquired. The vm_map_lock_upgrade() macro attempts to atomically upgrade a read-lock on map to an exclusive lock. The vm_map_lock_downgrade() macro attempts to downgrade an exclusive lock on map to a read-lock. IMPLEMENTATION NOTES
Currently, all of the locking macros implement their locks as sleep locks. SEE ALSO
vm_map(9) AUTHORS
This manual page was written by Bruce M Simpson <bms@spc.org>. BSD
July 19, 2003 BSD

Check Out this Related Man Page

VM_MAP_LOCK(9)						   BSD Kernel Developer's Manual					    VM_MAP_LOCK(9)

NAME
vm_map_lock, vm_map_unlock, vm_map_lock_read, vm_map_unlock_read, vm_map_trylock, vm_map_trylock_read, vm_map_lock_upgrade, vm_map_lock_downgrade -- vm_map locking macros SYNOPSIS
#include <sys/param.h> #include <vm/vm.h> #include <vm/vm_map.h> void vm_map_lock(vm_map_t map); void vm_map_unlock(vm_map_t map); void vm_map_lock_read(vm_map_t map); void vm_map_unlock_read(vm_map_t map); int vm_map_trylock(vm_map_t map); int vm_map_trylock_read(vm_map_t map); int vm_map_lock_upgrade(vm_map_t map); int vm_map_lock_downgrade(vm_map_t map); DESCRIPTION
The vm_map_lock() macro obtains an exclusive lock on map. The vm_map_unlock() macro releases an exclusive lock on map. The vm_map_lock_read() macro obtains a read-lock on map. The vm_map_unlock_read() macro releases a read-lock on map. The vm_map_trylock() macro attempts to obtain an exclusive lock on map. It returns FALSE if the lock cannot be immediately acquired; other- wise return TRUE with the lock acquired. The vm_map_trylock_read() macro attempts to obtain a read-lock on map. It returns FALSE if the lock cannot be immediately acquired; other- wise return TRUE with the lock acquired. The vm_map_lock_upgrade() macro attempts to atomically upgrade a read-lock on map to an exclusive lock. The vm_map_lock_downgrade() macro attempts to downgrade an exclusive lock on map to a read-lock. IMPLEMENTATION NOTES
Currently, all of the locking macros implement their locks as sleep locks. SEE ALSO
vm_map(9) AUTHORS
This manual page was written by Bruce M Simpson <bms@spc.org>. BSD
July 19, 2003 BSD

13 More Discussions You Might Find Interesting

1. OS X (Apple)

Mac OS X: Based on UNIX - Solid As a Rock

See this threads: Page Not Found - Apple Open Source - Apple (0 Replies)
Discussion started by: Neo
0 Replies

2. Tips and Tutorials

The Whole Story on #! /usr/bin/ksh

Introduction Originally, we only had one shell on unix. When ran a command, the shell would attempt to invoke one of the exec() system calls on it. It the command was an executable, the exec would succeed and the command would run. If the exec() failed, the shell would not give up, instead it... (3 Replies)
Discussion started by: Perderabo
3 Replies

3. BSD

FreeBSD Kernel Internals, Dr. Marshall Kirk McKusick

FreeBSD Kernel Internals, Dr. Marshall Kirk McKusick nwbqBdghh6E The first hour of Marshall Kirk McKusick's course on FreeBSD kernel internals based on his book, The Design and Implementation of the FreeBSD Operating System. (0 Replies)
Discussion started by: Neo
0 Replies

4. Tips and Tutorials

Unix File Permissions

Introduction I have seen some misinformation regarding Unix file permissions. I will try to set the record straight. Take a look at this example of some output from ls: $ ls -ld /usr/bin /usr/bin/cat drwxrwxr-x 3 root bin 8704 Sep 23 2004 /usr/bin -r-xr-xr-x 1 bin bin ... (6 Replies)
Discussion started by: Perderabo
6 Replies

5. Programming

Memory Leaks

Suppose I have a main() function with only one malloc statement allocating say some 1 gb memory. Also say my system has 1 gb of ram. main() { malloc(1gb) return(0) } The program above exits without freeing the memory. In this case will the 1 gb of heap memory be returned... (9 Replies)
Discussion started by: rupeshkp728
9 Replies

6. Shell Programming and Scripting

Scripts without shebang

I see lot of ad-hoc shell scripts in our servers which don't have a shebang at the beginning . Does this mean that it will run on any shell ? Is it a good practice to create scripts (even ad-hoc ones) without shebang ? (16 Replies)
Discussion started by: kraljic
16 Replies

7. Fedora

Is UNIX an open source OS ?

Hi everyone, I know the following questions are noobish questions but I am asking them because I am confused about the basics of history behind UNIX and LINUX. Ok onto business, my questions are-: Was/Is UNIX ever an open source operating system ? If UNIX was... (21 Replies)
Discussion started by: sreyan32
21 Replies

8. Web Development

A simple UNIXtime component in Vue.js

A shout out to Scott who gave me a helping hand to turn a simple sample Vue.js app I wrote yesterday into a Vue.js component: Vue.component("unix-time", { template: `<div class="time">{{unixtime}}</div>`, data() { return { unixtime: "" }; }, methods: { ... (1 Reply)
Discussion started by: Neo
1 Replies

9. Shell Programming and Scripting

Reason for no directory creation date

i read here that linux provides no way to determine when a directory was created. https://www.unix.com/shell-programming-and-scripting/157874-creation-date-directory.htmlI have a directory /home/andy/scripts that had a README file in it. That file says I put the script in that directory and... (3 Replies)
Discussion started by: drew77
3 Replies

10. Shell Programming and Scripting

Valid separator in time and date format

Hello. I can use any particular (stupid or not) format when using bash date command. Example : ~> date --date "now" '+%Y-%m-%d %H!%M!%S' 2019-06-03 12!55!33or ~> date --date "now" '+%Y£%m£%d %H¤%M¤%S' 2019£06£03 12¤57¤36 or ~> date --date "now" '+%Y-%m-%d %H-%M-%S' 2019-06-03 12-58-51 ... (4 Replies)
Discussion started by: jcdole
4 Replies

11. UNIX for Beginners Questions & Answers

UNIX Environment Setup - (Just starting!)

Morning All So, I am starting looking into the world of UNIX for a new job (luckily not my primary function!) and I am looking to get stared. Like anything I seem to learn best by trying things out first in an environment but I have a key question: Currently I use Oracle VirtualBox, can... (8 Replies)
Discussion started by: GophusMeau
8 Replies

12. Solaris

Is it safe to install x86 Solaris 10 U6 after installed-Linux-and-FreeBSD?

I've installed Slack 14.2 on /dev/sda1 (/dev/sda2 is swap) and FreeBSD 12 on /dev/sda3 and lilo is the boot manager. FreeBSD slices are as follows; / on /dev/ada0S3a, swap on /dev/ada0s3e, /var on /dev/ada0s3b, /tmp on /dev/ada0s3d and /usr on /dev/ada0s3f. I hesitate to install Solaris 10... (2 Replies)
Discussion started by: vectrum
2 Replies

13. Shell Programming and Scripting

Controlling user input

I'm trying to use a bash script for a psych experiment that involves listening to sound files and responding. If I have something like the code below, how can I make sure that a key press is assigned to RESPONSE only after the second echo statement? for i in 1 2 3; do echo "Ready?" sleep 2 ... (10 Replies)
Discussion started by: darwin_886
10 Replies

Featured Tech Videos