Running script twice at time
I'm making a little simple script to improve the efficienty of my work team.
The script simply searches a file that the user gives as param.
./check_file test_file.xml
I used only ls and cp commands and there's no log or temporary files.
My question is: should I put a .lock file to be sure that the script runs only once at time or can I avoid this control?
Usually I create a lock file, because my scripts write temporary files and if two users run at the same moment the script, it explodes.
Thanks!
linux bash
asked Nov 22 '18 at 22:11
Sebastiano GrassiSebastiano Grassi
31
add a comment |
I'm making a little simple script to improve the efficienty of my work team.
The script simply searches a file that the user gives as param.
./check_file test_file.xml
I used only ls and cp commands and there's no log or temporary files.
My question is: should I put a .lock file to be sure that the script runs only once at time or can I avoid this control?
Usually I create a lock file, because my scripts write temporary files and if two users run at the same moment the script, it explodes.
Thanks!
linux bash
asked Nov 22 '18 at 22:11
Sebastiano GrassiSebastiano Grassi
31
If your script has no side effects, don't bother with this kind of check.
– Antoine
Nov 23 '18 at 0:33
Even if your script does generate temporary files, you can always generate unique filenames so, even then, the lock would just be a matter of not using to much ressources (CPU, or IO).
– Antoine
Nov 23 '18 at 0:38
add a comment |
I'm making a little simple script to improve the efficienty of my work team.
The script simply searches a file that the user gives as param.
./check_file test_file.xml
I used only ls and cp commands and there's no log or temporary files.
My question is: should I put a .lock file to be sure that the script runs only once at time or can I avoid this control?
Usually I create a lock file, because my scripts write temporary files and if two users run at the same moment the script, it explodes.
Thanks!
linux bash
asked Nov 22 '18 at 22:11
Sebastiano GrassiSebastiano Grassi
31
I'm making a little simple script to improve the efficienty of my work team.
The script simply searches a file that the user gives as param.
./check_file test_file.xml
I used only ls and cp commands and there's no log or temporary files.
My question is: should I put a .lock file to be sure that the script runs only once at time or can I avoid this control?
Usually I create a lock file, because my scripts write temporary files and if two users run at the same moment the script, it explodes.
Thanks!
linux bash
linux bash
asked Nov 22 '18 at 22:11
Sebastiano GrassiSebastiano Grassi
31
asked Nov 22 '18 at 22:11
Sebastiano GrassiSebastiano Grassi
31
asked Nov 22 '18 at 22:11
Sebastiano GrassiSebastiano Grassi
31
asked Nov 22 '18 at 22:11
Sebastiano GrassiSebastiano Grassi
31
asked Nov 22 '18 at 22:11
Sebastiano GrassiSebastiano Grassi
31
31
If your script has no side effects, don't bother with this kind of check.
– Antoine
Nov 23 '18 at 0:33
Even if your script does generate temporary files, you can always generate unique filenames so, even then, the lock would just be a matter of not using to much ressources (CPU, or IO).
– Antoine
Nov 23 '18 at 0:38
add a comment |
If your script has no side effects, don't bother with this kind of check.
– Antoine
Nov 23 '18 at 0:33
Even if your script does generate temporary files, you can always generate unique filenames so, even then, the lock would just be a matter of not using to much ressources (CPU, or IO).
– Antoine
Nov 23 '18 at 0:38
If your script has no side effects, don't bother with this kind of check.
– Antoine
Nov 23 '18 at 0:33
If your script has no side effects, don't bother with this kind of check.
– Antoine
Nov 23 '18 at 0:33
Even if your script does generate temporary files, you can always generate unique filenames so, even then, the lock would just be a matter of not using to much ressources (CPU, or IO).
– Antoine
Nov 23 '18 at 0:38
Even if your script does generate temporary files, you can always generate unique filenames so, even then, the lock would just be a matter of not using to much ressources (CPU, or IO).
– Antoine
Nov 23 '18 at 0:38
add a comment |
1 Answer
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Generally speaking, no. I would recommend avoiding temporary files as much as possible, preferring pipes instead. However, I doubt it's always possible to avoid temporary files, so when I have to, I use $$ in the filename (current process ID or PID). So if you're using /tmp/check_file.tmp as your temporary filename, instead use /tmp/check_file.$$.tmp - then two processes can run at a time, each with their own PID, and not overlap.
Slightly more advanced is to also use ${TMP:-/tmp} as the temporary directory instead of just /tmp - that way users can specify a different directory for each run, and thereby also avoid any overlaps.
answered Nov 22 '18 at 22:20
TanktalusTanktalus
16k43262
add a comment |
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Generally speaking, no. I would recommend avoiding temporary files as much as possible, preferring pipes instead. However, I doubt it's always possible to avoid temporary files, so when I have to, I use $$ in the filename (current process ID or PID). So if you're using /tmp/check_file.tmp as your temporary filename, instead use /tmp/check_file.$$.tmp - then two processes can run at a time, each with their own PID, and not overlap.
Slightly more advanced is to also use ${TMP:-/tmp} as the temporary directory instead of just /tmp - that way users can specify a different directory for each run, and thereby also avoid any overlaps.
answered Nov 22 '18 at 22:20
TanktalusTanktalus
16k43262
add a comment |
Generally speaking, no. I would recommend avoiding temporary files as much as possible, preferring pipes instead. However, I doubt it's always possible to avoid temporary files, so when I have to, I use $$ in the filename (current process ID or PID). So if you're using /tmp/check_file.tmp as your temporary filename, instead use /tmp/check_file.$$.tmp - then two processes can run at a time, each with their own PID, and not overlap.
Slightly more advanced is to also use ${TMP:-/tmp} as the temporary directory instead of just /tmp - that way users can specify a different directory for each run, and thereby also avoid any overlaps.
answered Nov 22 '18 at 22:20
TanktalusTanktalus
16k43262
add a comment |
Generally speaking, no. I would recommend avoiding temporary files as much as possible, preferring pipes instead. However, I doubt it's always possible to avoid temporary files, so when I have to, I use $$ in the filename (current process ID or PID). So if you're using /tmp/check_file.tmp as your temporary filename, instead use /tmp/check_file.$$.tmp - then two processes can run at a time, each with their own PID, and not overlap.
Slightly more advanced is to also use ${TMP:-/tmp} as the temporary directory instead of just /tmp - that way users can specify a different directory for each run, and thereby also avoid any overlaps.
answered Nov 22 '18 at 22:20
TanktalusTanktalus
16k43262
Generally speaking, no. I would recommend avoiding temporary files as much as possible, preferring pipes instead. However, I doubt it's always possible to avoid temporary files, so when I have to, I use $$ in the filename (current process ID or PID). So if you're using /tmp/check_file.tmp as your temporary filename, instead use /tmp/check_file.$$.tmp - then two processes can run at a time, each with their own PID, and not overlap.
Slightly more advanced is to also use ${TMP:-/tmp} as the temporary directory instead of just /tmp - that way users can specify a different directory for each run, and thereby also avoid any overlaps.
answered Nov 22 '18 at 22:20
TanktalusTanktalus
16k43262
answered Nov 22 '18 at 22:20
TanktalusTanktalus
16k43262
answered Nov 22 '18 at 22:20
TanktalusTanktalus
16k43262
answered Nov 22 '18 at 22:20
TanktalusTanktalus
16k43262
16k43262
add a comment |
add a comment |
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If your script has no side effects, don't bother with this kind of check.
– Antoine
Nov 23 '18 at 0:33
Even if your script does generate temporary files, you can always generate unique filenames so, even then, the lock would just be a matter of not using to much ressources (CPU, or IO).
– Antoine
Nov 23 '18 at 0:38