.\" This manpage has been automatically generated by docbook2man .\" from a DocBook document. This tool can be found at: .\" .\" Please send any bug reports, improvements, comments, patches, .\" etc. to Steve Cheng . .TH "FCRONTAB" "1" "22 March 2025" "03/22/2025" "" .SH NAME fcrontab \- manipulate per-user fcrontab files which adhere to the format defined in fcrontab(5) .SH SYNOPSIS \fBfcrontab\fR [ \fB-c \fIfile\fB\fR ] [ \fB-n\fR ] \fB\fIfile\fB\fR [ \fB\fIuser\fB\fR | \fB-u \fIuser\fB\fR ] \fBfcrontab\fR [ \fB-c \fIfile\fB\fR ] [ \fB-n\fR ] { \fB-l\fR | \fB-r\fR | \fB-e\fR | \fB-z\fR } [ \fB\fIuser\fB\fR | \fB-u \fIuser\fB\fR ] \fBfcrontab\fR [ \fB-h\fR ] .SH "DESCRIPTION" .PP \fBFcrontab\fR is the program intended to install, edit, list and remove the tables used by \fBfcron\fR(8) daemon. As \fBfcron\fR internally uses a non-human readable format (this is needed because \fBfcron\fR saves more informations than the user gives, for example the time and date of next execution), the user cannot edit their \fBfcrontab\fR directly (the one used by \fBfcron\fR). .PP When a user installs a \fBfcrontab\fR, the source file is saved in the spool directory (\fI/var/spool/fcron\fR) to allow it to be edited, and a formatted file is generated for the \fBfcron\fR daemon. This formatted (non human readable) file with all recent changes included is then sent to the daemon. The daemon is not informed of the changes immediately but after some time to keep ill disposed users from blocking the daemon by installing \fBfcrontab\fRs over and over (i.e. denial of service attack). By default, the file is sent once per minute (about ten seconds before the full minute) to the daemon, the build time parameter \fB--with-max-fcrontab-reload-delay-seconds\fR can be used to specify a different maximum time to send this data. We will call "\fBfcrontab\fR" the source file of the \fBfcrontab\fR in the following. .PP The fcrontab files that a user modifies has to follow the format defined in \fBfcrontab\fR(5) \&. .PP Users can install a \fBfcrontab\fR if they are listed in \fI/etc/fcron.allow\fR and not listed in \fI/etc/fcron.deny\fR (see section "files" below). The keyword 'all' is a shorthand for all users. If neither \fIfcron.allow\fR nor \fIfcron.deny\fR exist, all users are allowed. None of these files have to exist, but if they do, the deny file takes precedence. .PP The first form of the command is used to install a new \fBfcrontab\fR file, from any named file or from standard input (if the pseudo-filename "-" is given), replacing the previous one (if any). Each user can have only one \fBfcrontab\fR\&. .PP For instance, root can create a systemwide fcrontab file, say \fI/etc/fcrontab\fR, and run "\fBfcrontab\fR \fI/etc/fcrontab\fR" to install the new version after each change of the file. Or root can create a new fcrontab running a simple "\fBfcrontab\fR", and then maintain it using "\fBfcrontab\fR \fB-e\fR". Same considerations apply to a non privileged user. .SH "OPTIONS" .TP \fB-u \fIuser\fB\fR Specify the user whose \fBfcrontab\fR will be managed, or "systab" for the system fcrontab. Should only be used by root. If not given, the \fBfcrontab\fR file of the user invoking \fBfcrontab\fR will be handled. It may be useful since the \fBsu\fR(8) command may confuse \fBfcrontab\fR\&. .sp .RS .B "Note:" the \&'\fIuser\fR\&' in the synopsys is equivalent to a '\fB-u\fR \fIuser\fR\&'. .RE .TP \fB-l\fR List user's current \fBfcrontab\fR to standard output. .TP \fB-e\fR Edit user's current \fBfcrontab\fR using either the editor specified by the environment variable \fBVISUAL\fR, or \fBEDITOR\fR if \fBVISUAL\fR is not set. If none or them are set, \fB/usr/bin/vi\fR will be used. .TP \fB-r\fR Remove user's \fBfcrontab\fR\&. .TP \fB-z\fR Reinstall user's \fBfcrontab\fR from its source code. All informations \fBfcron\fR may have kept in the binary \fBfcrontab\fR (such as the last execution time and date) will be forgotten (ie. lost). .TP \fB-n\fR Ignore previous version. If this option is not given, \fBfcron\fR will try to keep as much information as possible between old and new version of the \fBfcrontab\fR (time and date of next execution, if job is in serial queue, etc) if the line hasn't been modified (same fields, same shell command). .TP \fB-c \fIfile\fB\fR Make \fBfcrontab\fR use config file \fIfile\fR instead of default config file \fI/etc/fcron.conf\fR\&. To interact with a running \fBfcron\fR process, \fBfcrontab\fR must use the same config file as the process. That way, several \fBfcron\fR processes can run simultaneously on a single system. .TP \fB-d\fR Run in debug mode. In this mode, many informational messages will be output in order to check if anything went wrong. .TP \fB-h\fR Display a brief description of the options. .TP \fB-V\fR Display an informational message about \fBfcrontab\fR, including its version and the license under which it is distributed. .SH "RETURN VALUES" .PP \fBFcrontab\fR returns 0 on normal exit and 1 on error. .SH "CONFORMING TO" .PP Should be POSIX compliant. .SH "FILES" .TP \fB\fI/etc/fcron.conf\fB\fR Configuration file for \fBfcron\fR, \fBfcrontab\fR and \fBfcrondyn\fR: contains paths (spool dir, pid file) and default programs to use (editor, shell, etc). See \fBfcron.conf\fR(5) for more details. .TP \fB\fI/etc/fcron.allow\fB\fR Users allowed to use \fBfcrontab\fR and \fBfcrondyn\fR (one name per line, special name "all" acts for everyone) .TP \fB\fI/etc/fcron.deny\fB\fR Users who are not allowed to use \fBfcrontab\fR and \fBfcrondyn\fR (same format as allow file) .TP \fB\fI/etc/pam.d/fcron\fB (or \fI/etc/pam.conf\fB)\fR PAM configuration file for \fBfcron\fR\&. Take a look at pam(8) for more details. .SH "SEE ALSO" \fBfcrontab\fR(1), \fBfcrondyn\fR(1), \fBfcrontab\fR(5), \fBfcron.conf\fR(5), \fBfcron\fR(8). If you're learning how to use fcron from scratch, I suggest that you read the HTML version of the documentation (if your are not reading it right now! :) ): the content is the same, but it is easier to navigate thanks to the hyperlinks. .SH "AUTHOR" .PP Thibault Godouet