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diff --git a/man-pages-posix-2003/man3p/stat.3p b/man-pages-posix-2003/man3p/stat.3p new file mode 100644 index 0000000..f92ea96 --- /dev/null +++ b/man-pages-posix-2003/man3p/stat.3p @@ -0,0 +1,231 @@ +.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved +.TH "STAT" 3P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" stat +.SH PROLOG +This manual page is part of the POSIX Programmer's Manual. +The Linux implementation of this interface may differ (consult +the corresponding Linux manual page for details of Linux behavior), +or the interface may not be implemented on Linux. +.SH NAME +stat \- get file status +.SH SYNOPSIS +.LP +\fB#include <sys/stat.h> +.br +.sp +int stat(const char *restrict\fP \fIpath\fP\fB, struct stat *restrict\fP +\fIbuf\fP\fB); +.br +\fP +.SH DESCRIPTION +.LP +The \fIstat\fP() function shall obtain information about the named +file and write it to the area pointed to by the \fIbuf\fP +argument. The \fIpath\fP argument points to a pathname naming a file. +Read, write, or execute permission of the named file is not +required. An implementation that provides additional or alternate +file access control mechanisms may, under implementation-defined +conditions, cause \fIstat\fP() to fail. In particular, the system +may deny the existence of the file specified by \fIpath\fP. +.LP +If the named file is a symbolic link, the \fIstat\fP() function shall +continue pathname resolution using the contents of the +symbolic link, and shall return information pertaining to the resulting +file if the file exists. +.LP +The \fIbuf\fP argument is a pointer to a \fBstat\fP structure, as +defined in the \fI<sys/stat.h>\fP header, into which information is +placed concerning the file. +.LP +The \fIstat\fP() function shall update any time-related fields (as +described in the Base Definitions volume of +IEEE\ Std\ 1003.1-2001, Section 4.7, File Times Update), before writing +into the \fBstat\fP structure. +.LP +Unless otherwise specified, the structure members \fIst_mode\fP, \fIst_ino\fP, +\fIst_dev\fP, \fIst_uid\fP, \fIst_gid\fP, +\fIst_atime\fP, \fIst_ctime\fP, and \fIst_mtime\fP shall have meaningful +values for all file types defined in this volume of +IEEE\ Std\ 1003.1-2001. The value of the member \fIst_nlink\fP shall +be set to the number of links to the file. +.SH RETURN VALUE +.LP +Upon successful completion, 0 shall be returned. Otherwise, -1 shall +be returned and \fIerrno\fP set to indicate the error. +.SH ERRORS +.LP +The \fIstat\fP() function shall fail if: +.TP 7 +.B EACCES +Search permission is denied for a component of the path prefix. +.TP 7 +.B EIO +An error occurred while reading from the file system. +.TP 7 +.B ELOOP +A loop exists in symbolic links encountered during resolution of the +\fIpath\fP argument. +.TP 7 +.B ENAMETOOLONG +The length of the \fIpath\fP argument exceeds {PATH_MAX} or a pathname +component is longer than {NAME_MAX}. +.TP 7 +.B ENOENT +A component of \fIpath\fP does not name an existing file or \fIpath\fP +is an empty string. +.TP 7 +.B ENOTDIR +A component of the path prefix is not a directory. +.TP 7 +.B EOVERFLOW +The file size in bytes or the number of blocks allocated to the file +or the file serial number cannot be represented correctly +in the structure pointed to by \fIbuf\fP. +.sp +.LP +The \fIstat\fP() function may fail if: +.TP 7 +.B ELOOP +More than {SYMLOOP_MAX} symbolic links were encountered during resolution +of the \fIpath\fP argument. +.TP 7 +.B ENAMETOOLONG +As a result of encountering a symbolic link in resolution of the \fIpath\fP +argument, the length of the substituted pathname +string exceeded {PATH_MAX}. +.TP 7 +.B EOVERFLOW +A value to be stored would overflow one of the members of the \fBstat\fP +structure. +.sp +.LP +\fIThe following sections are informative.\fP +.SH EXAMPLES +.SS Obtaining File Status Information +.LP +The following example shows how to obtain file status information +for a file named \fB/home/cnd/mod1\fP. The structure variable +\fIbuffer\fP is defined for the \fBstat\fP structure. +.sp +.RS +.nf + +\fB#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +.sp + +struct stat buffer; +int status; +\&... +status = stat("/home/cnd/mod1", &buffer); +\fP +.fi +.RE +.SS Getting Directory Information +.LP +The following example fragment gets status information for each entry +in a directory. The call to the \fIstat\fP() function +stores file information in the \fBstat\fP structure pointed to by +\fIstatbuf\fP. The lines that follow the \fIstat\fP() call +format the fields in the \fBstat\fP structure for presentation to +the user of the program. +.sp +.RS +.nf + +\fB#include <sys/types.h> +#include <sys/stat.h> +#include <dirent.h> +#include <pwd.h> +#include <grp.h> +#include <time.h> +#include <locale.h> +#include <langinfo.h> +#include <stdio.h> +#include <stdint.h> +.sp + +struct dirent *dp; +struct stat statbuf; +struct passwd *pwd; +struct group *grp; +struct tm *tm; +char datestring[256]; +\&... +/* Loop through directory entries. */ +while ((dp = readdir(dir)) != NULL) { +.sp + + /* Get entry's information. */ + if (stat(dp->d_name, &statbuf) == -1) + continue; +.sp + + /* Print out type, permissions, and number of links. */ + printf("%10.10s", sperm (statbuf.st_mode)); + printf("%4d", statbuf.st_nlink); +.sp + + /* Print out owner's name if it is found using getpwuid(). */ + if ((pwd = getpwuid(statbuf.st_uid)) != NULL) + printf(" %-8.8s", pwd->pw_name); + else + printf(" %-8d", statbuf.st_uid); +.sp + + /* Print out group name if it is found using getgrgid(). */ + if ((grp = getgrgid(statbuf.st_gid)) != NULL) + printf(" %-8.8s", grp->gr_name); + else + printf(" %-8d", statbuf.st_gid); +.sp + + /* Print size of file. */ + printf(" %9jd", (intmax_t)statbuf.st_size); +.sp + + tm = localtime(&statbuf.st_mtime); +.sp + + /* Get localized date string. */ + strftime(datestring, sizeof(datestring), nl_langinfo(D_T_FMT), tm); +.sp + + printf(" %s %s\\n", datestring, dp->d_name); +} +\fP +.fi +.RE +.SH APPLICATION USAGE +.LP +None. +.SH RATIONALE +.LP +The intent of the paragraph describing "additional or alternate file +access control mechanisms" is to allow a secure +implementation where a process with a label that does not dominate +the file's label cannot perform a \fIstat\fP() function. This +is not related to read permission; a process with a label that dominates +the file's label does not need read permission. An +implementation that supports write-up operations could fail \fIfstat\fP() +function calls +even though it has a valid file descriptor open for writing. +.SH FUTURE DIRECTIONS +.LP +None. +.SH SEE ALSO +.LP +\fIfstat\fP(), \fIlstat\fP(), \fIreadlink\fP(), \fIsymlink\fP(), +the Base Definitions volume of +IEEE\ Std\ 1003.1-2001, \fI<sys/stat.h>\fP, \fI<sys/types.h>\fP +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of +Electrical and Electronics Engineers, Inc and The Open Group. In the +event of any discrepancy between this version and the original IEEE and +The Open Group Standard, the original IEEE and The Open Group Standard +is the referee document. The original Standard can be obtained online at +http://www.opengroup.org/unix/online.html . |